part II

.) places them in the _Limacodidae_. They are small black, grey or brown moths, with small eyes; no ocelli; the palpi wanting or very minute, and the mouth parts little developed. They have remarkable parasitic habits in the caterpillar state living upon the backs of different leaf hoppers (_Homoptera_) and feeding upon the waxy or sugary secretions discharged by their hosts. Perkins describes 7 new Australian species, which are placed in three genera, based on the neuration of the wings. Three species come from Cairns, N. Queensland, and four from the neighbourhood of Sydney. _Heteropsyche melanochroma_ measures under ½ an inch across the outspread wings and is of a general black or fuscous colour with purple tints on the fore wings. Koebele records it as common about Sydney, parasitic upon a number of different Fulgorids and Jassids.

Rothschild (Novitates Zoologicae 1906) has named another species, _Epipyrops doddi_, after the well known collector, P. F. Dodd, who had worked out its life history in North Queensland.

[Illustration: =Fig. 145.=--_Plodia interpunctella_ (Hubner).]

Order VII.--DIPTERA.

Flies.

House flies are well known to everyone; but as a number of other insects belonging to different orders are often called flies, such as “saw-flies,” which are Hymenoptera, and “lace-winged flies” and “May-flies,” which are Neuroptera, it is advisable to define them. Some of the Diptera might be mistaken by a casual observer for Hymenoptera which the members of several families often mimic in form and colouration, but they can be readily separated by the absence of a second pair of wings, which are represented by two little clubbed processes, known as balancers, poisers, or halteres. The mouth parts are very variable in structure in the different groups, but always adapted for piercing or sucking; the eyes are large, often occupying the greater part of the head and consisting of an immense number of fine facets; the small ocelli are three in number; and the antennae, except among midges, are short, composed of few joints, and often terminate in a bristle.

The thorax is not so distinctly divided into the three segments as in some other insects, nor the parts so well defined as in the hymenoptera; the wings, transparent or parchment-like, are seldom coloured; the legs, usually not thickened, are furnished with five tarsi, and well developed claws, with a small pad under each, known as the pulvillus. The abdomen is composed of a variable number of segments ranging from four to nine, but in the former case though not visible the terminal ones are probably absorbed into the anal tube at the extremity. Most diptera are brown, black, or grey, though metallic tints predominate in some families; and are clothed with short scattered hairs or bristles.

The typical fly larva is an elongated legless maggot with the head portion slender, enclosing a pair of black retractile hooked jaws, with tracheae opening behind and running through to the broadened anal segment where they form small rosette-like processes round the external aperture. The eggs are laid in all kinds of decaying vegetable or animal matter, with the exception of the few that produce galls, or otherwise damage plant tissue; when full grown they change into a hard shell-like chrysalis, the tip of which is pushed off by the perfect fly when ready to emerge.

Though this country is very rich in Diptera and many cosmopolitan species have been introduced such as the house flies, they have been much neglected by Australian collectors and entomologists. The Diptera are divided into two large sections, which are further subdivided into four main groups, to which a fifth has been lately added for the reception of the fleas, which however are often placed by specialists in a class by themselves (_Siphonaptera_). The older writers subdivided them into about 70 families but latterly these have been reduced, and most of our species will come under about 30 families, of which I can only note our most striking representatives.

In 1830 the French naturalist Robineau Desvoidy published his “Essai sur les Myodaires,” in which some of our species were described. Between the years 1834 and 1835 Macquart brought out his “Histoire naturelle des Insectes Diptères” (forming part of the great French work Suites à Buffon), followed (1838–42) by his “Diptères exotiques, nouveaux ou peu connus” comprising two volumes and many plates, with 5 supplements (1846–55). Walker between 1848 and 1855 compiled a “Catalogue of the Diptera of the British Museum” consisting of 7 volumes; and others are described in his “Diptera Saundersiana” 1856.

In 1864 Dr. Schiner estimated that the number of described Australian Diptera was 1056, including those which he described (Diptera des Novara), collected by Frauenfeld in the neighbourhood of Sydney during the visit of the Austrian Frigate. In a long series of papers reaching from 1859 till just before his death in 1892 Bigot described a great many species (among them some from Australia) chiefly in the Annales de la Societé Entomologique de France.

The only systematic Australian work is Skuse’s “Monograph of the Australian Diptera” (Pro. Linn. Soc. N.S.W. 1888–90), which however was never completed, dealing only with the NEMATOCERA comprising the Culicidae, Tipulidae, Cecidomyidae and some of the smaller families. There is no complete catalogue of Australian Diptera, but I have been greatly assisted in my work on this family through the identification of my specimens by Mr. Coquillett of Washington.

Family 1. Gall-Gnats.

CECIDOMYIDAE.

This is an extensive family of small delicate midges with long slender antennae composed of many bead-like segments beautifully feathered with whorls of hairs. The abdomen is stout at the base, short and tapering to the tip; the legs are long and slender without spurs; the wings are clothed with fine hairs that easily rub off, and furnished with very few longitudinal veins, and in some genera only one cross nervure.

They are known as “Gall-gnats,” or “Gall-flies,” and though the habits of the larvae are very diverse, some living under bark, others in animal matter, and a few predaceous or even cannibalistic in their habits, the majority of them are found in plant tissue and produce malformations or regular well defined galls, often of very remarkable structure, upon the foliage or twigs of their food plant.

The egg is deposited in or under the bark, epidermis of the leaf, or frequently in the flower buds of plants, the irritation caused by the active larvae producing the aborted tissue. These larvae are very easily recognised if examined with a lens after they have been extracted from the gall, as they are furnished with a “breast bone,” an anchor shaped process that stands out very distinctly in the centre of the ventral surface and is unknown in the larvae of any other gall-producing insect.

Through the discovery of Wagner, a Russian entomologist, that the larva of a Cecidomyia produced young; also through the curious exudations of the larvae and pupae of others which are sometimes called “flax seed” from their shape; and the very destructive habits of several species which damage the wheat, like the Hessian Fly in America, this family has received a great deal of attention. Over 1,000 species have been described from all parts of the world, and Australia is particularly rich in these insects. Skuse (Pro. Linn. Soc. N.S.W. 1888 and 1890) has described over 100 species and figured some of the most peculiar galls.

_Cecidomyia frauenfeldi_ was named by Dr. Schiner after the naturalist who collected the galls on _Leptospermum_ in the vicinity of Manly, N.S. Wales. These galls are produced upon a leaf-bud and consist of a number of rounded leaf-like bracts, not unlike the petals of a rose bud; folding over each other, brown in colour, soft and loose, and about the shape and size of a small marble. The enfolded larva will be found in the base at the centre, and the gnats can be easily bred out in a glass jar. The Acacia Gall-gnat, _C. acaciae-longifoliae_, infests the flowers of this wattle, depositing its eggs in such numbers that every tiny seed-pod is produced into a contorted mass of finger-like tubes, together forming a rounded base attached by a stalk, and each tube containing a larva. This is one of our commonest species and the galls can often be collected in numbers in the neighbourhood of Sydney.

_Diplosis frenelae_ produces very remarkable little light brown spherical structures upon the tips of the foliage of the desert cypress, about the size of small peas; these when mature split into four shell-like sections, quite unlike the usual gall. They are very abundant in the early summer upon cypresses in Wagga and the western pine scrubs of N.S. Wales. _Diplosis paralis_ forms curious little blisters upon the young foliage of _Eucalyptus corymbosa_, dotting the leaves all over with reddish spots with a keyhole-like mark on the apex. A third species, _D. eucalypti_, aborts the young twigs of Eucalypts into gouty swellings in which a number of larvae feed and pupate.

There are certain red rounded shot-like galls of the Eucalyptus, generally several in number on the midrib of the leaf, which, on account of the pupal skins always remaining in the holes in the sides of the galls through which the flies have escaped, can be easily distinguished from many very similar ones that are the work of micro-hymenoptera. These are formed by a large stout gnat named _Hormomyia omalanthi_ by Skuse, who first obtained specimens from galls on the under side of the leaves of _Omalanthus populifolius_.

_Lasioptera miscella_ aborts the leaf stalks of _Eucalyptus haemastoma_, one of our white stemmed gums growing about Botany, N.S.W., with its irregular swellings.

I have also bred several undetermined species from galls on the twigs of the Weeping Myall, _Acacia pendula_, and other wattles in the western scrubs. There is a rich field awaiting the naturalist who takes up the study of the life-history of our Gall-gnats.

Though the Hessian Fly, _Cecidomyia destructor_, is not known in Australia it has been introduced into New Zealand, and in the United States of America is one of the most serious pests that the wheat farmers have to fight. This gnat deposits her eggs under the sheath of the growing wheat stalks; the larva sucks up the sap, so that the ear is impoverished and no grain forms in the head; and when they are numerous the greater part of the crop is destroyed.

Family 2. Shade Midges.

MYCETOPHILIDAE.

These small flies, popularly known as “Midges,” are placed by Skuse in four well defined families, which I place under the one heading as their habits are very similar.

The SCIARIDAE are the typical “Shade midges” infesting forest country; their larvae live under dead bark or decomposing leaves and are slender, cylindrical, semi-translucent maggots, white or pale yellow in colour, with the body composed of 13 segments including the head. The perfect insects have moderately long, curved, many jointed antennae; two ocelli; long slender legs; and the wings often clouded. Skuse has described 42 species in this group, all of which with one exception he placed in the typical Genus _Sciara_; these have the wings longer than the abdomen, the surface of them microscopically pubescent, and the wing-lobes more or less developed.

The MYCETOPHILIDAE are popularly known as “Fungus-midges” from the fact that the larvae, which are slender white maggots attenuated at both extremities, and with horny heads, are often found feeding upon the juices of fungi; some spin silken webs under which they live, and a few are said to be luminous. They are small flies with beautifully marked wings in many species, and have slender antennae; 3 ocelli; and a short proboscis; the rather long legs have the coxae elongated and are furnished with spurs upon the tibiae; the wings, without a discoidal cell, have more veins than those of the Gall-gnats. Walker described 4 species (Insecta Saundersiana 1856); to which Skuse added 31 new species. _Lyomya setiosicaudata_ was described by Skuse from the neighbourhood of Sydney in the Genus _Acrodicrania_, but it has an extended range: I have taken it with a sweeping net about Inverell N.S. Wales. It measures about ⅙ of an inch in length; has a shining head and thorax; abdomen black, and variegated black and yellow legs.

The SIMULIDAE contains a number of small Diptera abundant in Europe and America, where they are known as “Sand-flies,” “Black-flies,” or “Buffalo-gnats”; they swarm in the marshy lands of the Mississippi where Howard says, “They rival the mosquito in their blood-thirsty tendencies, and not only do they attack human-beings, but poultry and domestic animals are frequently killed by them.” We are fortunate in having very few of these pests; only one species was discovered by Skuse, who named it _Simulium furiosum_, and says it is a rare fly only found in the Gosford district N.S. Wales. These flies must not be confounded with the midges known in Australia as “Sand-flies,” which are very different insects belonging to the Genus _Ceratopogon_, of the Family Chironomidae.

The BIBIONIDAE are medium sized flies with thickset bodies somewhat hairy; smoky wings; robust legs; short antennae; and three ocelli. The females deposit their eggs in dung or vegetable matter, and the maggots have rows of transverse bristles on the segments; and traces of eyes can be found in the head segment. The perfect flies are sluggish in their movements and are commonly found upon flowers. Twelve species have been described from Australia, of which _Bibio imitator_ is our commonest species; it is very abundant in the early summer upon the flower heads of _Astrotricha floccosa_, which grows in most of the valleys round Sydney; it has a wide range from Tasmania northwards in similar forest country. The male is under ½ an inch in length and is of a uniform black tint, with the thorax dull red; while the larger female is of a uniform reddish brown, and both sexes have the typical dark clouded wings.

The South American Genus _Plecia_ is represented by four species, two of which I collected in North Queensland. The North American Genus _Scatopse_, the larvae of which breed in all kinds of decaying matter and in sewers, is represented by two species, of which _Scatopse fenestralis_ is so common about Sydney that Skuse says: “In the spring months it is scarcely possible to find a window without one or two specimens, while I have frequently seen hundreds swarming on the inside of shop windows in the city.”

Family 3. Mosquitoes.

CULICIDAE.

No insect pests are better known or more world wide in their distribution than mosquitoes. As might be expected, they are abundant in tropical countries, yet one would hardly expect them to be much of an annoyance in the temperate regions. Yet in Lapland, and even farther north, they worry the inhabitants and the reindeer all through their brief summer.

[Illustration: Plate XXVII.--DIPTERA.

Family CULCIIDAE.

1. _Culex fatigens_ (Wiedermann). Larva. 2. _Culex fatigens_ (Wiedermann). ♀. 3. _Culex fatigens_ (Wiedermann). Wing. 4. _Anopheles annulipes_ (Walker). ♀. 5. _Anopheles annulipes_ (Walker). Wing.]

[Illustration: _Plate XXVII.--DIPTERA._]

They are insects with long slender legs; delicate narrow wings folded down over an elongate body; the head is provided with a proboscis projecting below. The proboscis is adapted for sucking blood, though many of the bush species seldom or never taste blood and obtain their nutriment from the sap or moisture upon plants. The male mosquito is a more delicate creature than the female, furnished with plumose antennae; he does not bite, but hides away in dark sheltered corners taking no food in his short life of four or five days, but has a low droning hum, noticeable when a number are disturbed. The larger females on the other hand swarm into the house, and bite whenever they get the chance. She lays her eggs in little boat shaped masses of elongate eggs, which within 24 hours give birth to larvae that are often called water-fleas or “wrigglers.” Thread-like in form at first, the “wriggler” has a rounded ciliate head, and the tip of the body is provided with a pair of tubular breathing appendages. They move about with a series of jerks, always coming to the surface head downward; they increase in size rapidly and in seven or eight days are full grown, when they change into pupae, the creatures becoming quite different; the head and thorax are drawn up into a rounded mass with two trumpet shaped horns, which are its new breathing tubes, rising upon the sides. The abdominal segments are short and turn downward; and though it does wriggle slightly, it usually rests in an upright position floating close to the surface; it remains in this state for two or three days, when the pupal skin splits along the top of the head, and the perfect insect emerges, using the floating skin as a raft from which to rise into the air and fly away.

Only 9 species of mosquitoes had been described from Australia when Skuse commenced his work on these insects in the Macleay Museum Collections (Pro. Linn. Soc. N.S.W. 1889), where he listed all the known species and added 19 new ones. Since then Theobald, in his “Monograph of the Culicidae of the World” 1900–1903, with a great deal more material to study, revised the genera, made several of Skuse’s species synonymous, and described others, bringing our list to about 34 species.

The typical Genus _Culex_ contains 21 species scattered all over Australia; several are cosmopolitan and have been introduced from abroad. Our common house mosquito, that appears in the early summer, is _Culex albo-annulatus_, a moderate sized species with the reddish thorax densely clothed with brownish golden scales, traversed by five very fine lines; it has regularly white banded legs. It was described by Macquart in 1732, and ranges from Southern Queensland to Sydney, Mittagong, and the Blue Mountains N.S.W. _Culex fatigans_ is widely distributed over Australia: _C. macleayi_ and _C. skusei_ according to Theobald are only sub-species or varieties; it is one of the cosmopolitan mosquitoes also found in America, Africa and Asia, and was probably introduced into this country in the water tanks of the old sailing vessels many years ago. After New Year a smaller, darker mosquito is the most annoying about Sydney; this has been described by Theobald under the name of _Culex marinus_; its larvae were discovered by Dr. Bancroft, Queensland, breeding in salt water. It also flourishes freely in any stagnant water left in tanks, buckets, or water-holes, and has a wide range down our eastern coast.

Four species of the Genus _Anopheles_ are found in Australia; these insects have long palpi with clubbed or spatulate tips, and dark spotted wings. _Anopheles annulipes_, described by Walker, said to be identical with Skuse’s _A. musivus_, is found about Sydney and Newcastle N.S.W. ranging northward; the members of this genus are well known as the mosquitoes that transmit the germs of malarial fever, and have a wide range over the world. The important results that have come from the study of the relation of tropical fevers to mosquito bites, have led to the collection and description of these insects from all quarters of the globe. _Mucidus alternans_, one of our largest species, is thickly clothed with grey and light brown scales and hairs which give it a striking appearance. It is a day flying species famous for its biting powers; it has a wide range; in the Maitland district N.S.W. about the Hexham swamps it is locally known as the “Hexham Grey”; in Queensland it is sometimes called the “Scotch Grey.” I have also taken it at Bourke on the Darling River N.S.W. Skuse described this species as _Culex hispidosus_, but Westwood’s name, _C. alternans_, has a prior claim.

_Stegomyia notoscriptus_ is one of the small dark mosquitoes that bite so sharply just at dusk in our gardens around Sydney in midsummer, and has a wide range from Adelaide S.A. to Queensland. It belongs to the same genus as the dreaded Cuban Yellow-fever Mosquito, _Stegomyia fasciata_, which has been introduced into Hawaii. Theobald has in the last volume of his Monograph formed a new Genus _Skusea_ for the reception of two Queensland species and a third from Africa.

Family 4. Sand-flies.

CHIRONOMIDAE.

This group comprises a number of small flies which have the head furnished with a fleshy proboscis; the slender antennae adorned with fine hairs, thickest upon the male; and the ocelli wanting. Their wings are usually narrow; and many of the large species have the general appearance of mosquitoes.

The members of this family are very extensive and world-wide in their range; the larvae of the typical Genus _Chironomus_ live chiefly in stagnant water. They sometimes swarm in such numbers in the North American lakes that they form the chief food of the fresh-water fish. In England on account of their colour they are known as “blood-worms.” Some species live in salt water, and others breed in excrement and dung. The perfect insects are easily collected with a sweeping net in the vicinity of swamps and watercourses.

Skuse has described 64 species from Australia (Pro. Linn. Soc. N.S.W. 1889), previous to which only 8 species, described by Messrs. Walker and Macquart, had been recorded. The family is divided into a number of genera, of which _Chironomus_ includes 21 species of the more typical slender-bodied midges, and the Genus _Ceratopogon_ 17 species of our vicious “Sand-flies.” These pests are also found in Great Britain and in North America, ranging as far south as Chili.

_Ceratopogon molestes_, described by Skuse, is our common “Sand-fly,” though there are others probably quite as annoying if not so abundant. It is a tiny little dark coloured midge, so quiet and small that it is usually felt before it is seen. There is another very large grey “Sand-fly” I have met with in the interior of N.S. Wales on the Darling River that frequents grassy watercourses and flies straight at the hands or face like a wasp.

It has been reported from Central Queensland that after the great flood and abundant growth of grass (1905) the sand-flies increased in such numbers, that they caused the blindness and death of a great number of marsupials, through biting them in the eyes.

Family 5. Crane-flies.

TIPULIDAE.

The Crane-flies or Daddy-longlegs are a large family with long slender legs, from which they take their popular names, and might be described as exaggerated mosquitoes that do not bite. They have the usual small head and long thread-like antennae (in some groups the latter are clothed with long hairs, in others short and feathered); in most species the ocelli are wanting. The thorax has a V-shaped transverse suture, and the well developed wings have a complete venation. They are to be found in all situations among low scrub, but prefer the shelter of cliffs, or tree trunks in damp gullies, often resting in considerable numbers in retired spots during the day, where they can easily be captured. They require to be killed and mounted in the place of capture to secure good specimens, as their legs drop off very readily, and on this account are not a popular group with the ordinary collector. The larvae live in the ground or among decaying vegetable matter.

They are divided into two large groups, characterised by the possession of long or short palpi, the _Tipulidae brevipalpi_ and _Tipulidae longipalpi_; about 20 species had been recorded from Australia when Skuse’s Monograph, “Diptera of Australia Pt. VII.” (Pro. Linn. Soc. N.S.W. 1889) appeared; in this he added over 80 new species.

The Painted Crane-fly, _Gynoplistia bella_, described by Walker in 1835, is one of our commonest species, frequenting flowers and low scrub in the early summer months. It is a very distinctly marked black and orange yellow fly, the wings thickly barred and mottled with the former colour; and is one of the short-legged species. It has a wide range from Western Australia and Tasmania to N.S. Wales; the genus is represented by 17 described species in Australia.

The Long-horned Crane-fly, _Macromastix costalis_, has a wide range from Tasmania to Queensland. In the neighbourhood of Sydney they are commonly found resting among the low scrub. It has a uniform dull brown tint with clear transparent wings, striped along the front margin with dull brown, and can be easily recognised from its large size, with the long slender antennae three times the length of the wings in the male, and its curious darting flight when disturbed. It was described by Swederus as _Tipula costalis_ in 1787, and has been renamed half a dozen times since. _Clytocosmus helmsi_ was described by Skuse from specimens obtained at Mt. Kosciusko; it is a large handsome fly with the stout thickened abdomen black, and bordered or mottled along the segments with white; the wings are semitransparent shaded with yellow; the head and thorax are reddish yellow.

The Genus _Semnotes_ contains two very large and handsome crane-flies, both of which were originally described by Westwood. They are giants of the family, with a large thorax, and swollen abdomen narrowed slightly into a waist, coming out broad and rounded to the tip; the general colour is bright yellow mottled with black, with semitransparent wings. _Semnotes ducalis_ has dark markings on the wing, and is the rarer species. It is recorded by Westwood from North Australia, and by Skuse from Manly, N.S.W. _S. imperatoria_ is found in Victoria, about Sydney and the Blue Mountains N.S.W.; it is slightly larger than the former, and can be easily distinguished by the very long tarsi, the plain wings, and the different markings on the body.

Family 6. Soldier Flies.

STRATIOMYIDAE.

These are flat-bodied flies with narrow strongly veined wings; 3-jointed antennae; and the pronotum furnished with slender spines. Comstock has called them “Soldier Flies” on account of the bright coloured stripes with which many species are marked. The larvae of most of these flies live in decaying vegetable matter, but some are known to be carnivorous in their habits.

_Neoexaireta spinigera_ is one of our commonest species, often to be found in the early summer months resting on the window pane with its broad hind legs flattened out; it is very easily captured. It is a slender shining black fly about 1 inch in length, with banded legs; the sides of the body fringed with white hairs, and the apical half of the wings clouded with black enclosing a small white blotch; the pronotum is furnished with four slender spines standing out from the hind margin. The larvae are usually found under damp rotting bark or decaying vegetable matter, and are elongate flattened brownish and distinctly segmented creatures, with narrow horny heads standing out in front like a stalk; they are sluggish creatures with very little movement. I figured and described a species (doubtfully) under the name of _Ephippium albitarsis_ in my “Entomology of the Grass-trees” (Pro. Linn. Soc. N.S.W. 1896) with somewhat similar larvae breeding in the decaying stems of these trees. The little black fly measures about ⅓ of an inch in length; it has white tarsi and dusky wings; the pronotum has the usual short spine on either side; and the legs are stout. _Odontomyia stylata_ is an elongate, broad, flattened, bronzy green fly with the outer edges of the abdomen light green; and the long pointed wings are folded down over the back; the head is very broad; the rounded thorax is long, furnished with two small spines behind the pronotum, and the abdomen is broadly rounded at the tip. It is a common rather large fly about ½ an inch in length, usually found resting on foliage in damp places. It has a wide range over Australia. In other parts of the world these flies are numerous, and about 1,000 species of the family have been described.

Family 7. March Flies.

TABANIDAE.

These flies are large or moderate sized insects, with broad heads furnished with a fleshy proboscis well adapted for biting; the 4-jointed antennae stand out in front of the head and do not terminate in a bristle; in the male the large eyes meet in front, but in the female are separated; the wings are large, often long, and well adapted for flight; the legs moderately stout; and the abdomen long, broad, and somewhat flattened.

They are common in the early summer months in open forest country, and are popularly known in Australia as “March Flies”; in England and America they usually go under the name of “Horse or Gad Flies,” and are a great pest to both man and horse; they are so persistent in their endeavours to bite and suck up blood that they are very easily captured with the hand.

The larvae of TABANIDAE live in damp earth, or are found in water; they are carnivorous, feeding upon larvae and pond snails. The flies deposit their eggs in bunches on herbage or low shrubs. These flies are very interesting from an economic point of view, for they are said to be sometimes responsible for outbreaks of anthrax by introducing the bacillus when biting. Some years ago an outbreak of malignant pustules on cattle in New Caledonia was said to have been traced to an undetermined species of _Pangonia_ (Megnin and Germain, Bulletin Soc. Ent. France Vol. viii. ser. 5).

The Genus _Pangonia_ is well represented in this country by many large handsome flies that differ from the typical _Tabanus_ in having ocelli, and the third joint of the antennae elongate instead of compressed. _Pangonia guttata_ was figured by Donovan in his “Insects of New Holland”; it measures over 1 inch in length, and is broad in proportion; its general colour is black, clothed with little tufts of white downy hairs fringing the thorax in front of the wings, and forming a band round the outer edge, with similar spots down the centre of the abdominal segments; the under-surface is variegated with longer white and black hairs, and the wings are clouded with black. This large handsome fly is common in the coastal forests, usually found resting on tree trunks in the heat of the day. _P. rufovittata_ is a smaller more showy insect of a dull yellow colour. The eyes, parallel markings on the thorax, and broad transverse bands on the abdomen of black, the alternate abdominal bands of beautiful golden hairs, together with the yellow clouded wings, give it a very striking appearance; it also has a wide range over Australia, and is occasionally taken in the neighbourhood of Sydney. _P. auriflus_, about ½ an inch in length, also black, has the face, front of thorax, under-surface and outer margins of the abdomen clothed with silvery hairs, while the hind margin of the thorax, a blotch in the centre, and the tip of the abdomen are richly coloured with bright yellow hairs. _P. concolor_, a much larger fly, is of a uniform reddish brown colour, with black eyes, and mottled wings; _P. violacea_ is a small bright metallic violet tinted insect not unlike a blue bottle fly, but is easily distinguished when the antennae are examined.

The Genus _Tabanus_ contains many of the typical “March Flies”: _Tabanus brevidentatus_ measures ½ an inch in length; is of a uniform grey ash colour, with the hind edges of the abdominal segments barred with light brown. _T. edentulus_ is a slightly larger, darker coloured fly with greyer bands on the body; it is common on the slopes of Mt. Kosciusko. _T. abstersus_ is still larger and darker, but with the same general colour; the head and under-surface are clothed with white hairs; the wings clouded; the base and sides of the abdomen reddish brown with the dorsal surface barred with fine white hairs. _T. sanguinarius_, one of the largest species, is of a uniform reddish brown, with black eyes; the thorax tinted with yellow; and the wings clouded. It has a wide range over Queensland and N.S. Wales. _Silvius angusta_ is like a very small specimen of _Tabanus brevidentatus_.

The members of the small Family LEPTIDAE are distinguished from the preceding one, in having the third joint of the antennae simple and furnished with a bristle, and the tibiae spined. The curious looking larvae have the abdomen divided into two points at the tip; they live in pits like the ant-lions. _Leptis aequalis_ is a greyish looking species about the size of a house fly, with the head composed of two large globular eyes touching in the centre; the legs are long; the wings smoky; the elongated abdomen rounded at the tip, and barred with black; the whole insect clothed with scattered hairs standing up thickly on the dorsal surface. These flies are very common flying over aphis infested wheat fields; my specimens come from Molong, N.S. Wales.

Family 8. Bee-flies.

BOMBYLIDAE.

These are popularly known as bee-flies, on account of their remarkable powers of flight, and hairy appearance. They are all more or less clothed with delicate downy hairs, furnished with 3 jointed antennae, and slender legs terminating in fine claws.

They frequent flowers, hovering over them like bees; and many species have the wings richly marked with black. The life history of our species is but little known, but I have bred several out of the clay nests of wasps, and two out of lepidopterous pupae (_Agrotis sp._). A European species is said to drop her eggs upon the clay nests of wasps; the newly hatched larva is furnished with a boring apparatus in front of its head by means of which it works its way through into the chamber; there it undergoes another stage of development and emerges from it with a simple sucking mouth to eat up the wasp larva. The larva of those attacking the “cut-worms,” _Agrotis_, devours the whole of the moth grub and pupates inside the chrysalid skin. The pupa is a very curious looking creature enclosed in a dark brown shining skin about ¾ of an inch long, with projecting spines on the head and extremity. The body is cylindrical with the first 7 segments furnished with a band of rasp-like spines or ridges on the dorsal surface, with which it moves round and round when touched. _Anthrax nigricosta_ is a handsome little black fly, with the head, under surface of the body, and two bands across the abdomen fringed with white down. The wings are deeply marked with black on the front margin, widest at the base. It measures about ½ an inch in length, and comes from Queensland. _Comptosia albo-fasciata_ is a large black fly shaded with fine reddish hairs on the dorsal surface of the body; the wings are brown, very long, with white tips; the body measures about ¾, and across the outspread wings 1½ inches. _Neuria quadripennis_ is a much smaller, but somewhat similar looking fly, with the dorsal surface and margins of the body more hairy; each wing is darkly clouded, with the base light, and the tip white. Both these species are not uncommon in New South Wales.

_Acreotrichus gibbicornis_ is a beautiful little black fly with brown eyes; not much over ¼ of an inch long; the elongate antennae and head are clothed with tufts of black and white down; the rest of the body is enveloped in long silvery white down. _A. fuscicornis_ is of a rich violet black tint, a yellow line round the hind margin of the head, and a broader band round the dorsal margin of the thorax of a similar colour; the broad rounded abdomen is lightly banded with pubescence. These flies were taken in numbers hovering over the flowers of plum-trees in an orchard near Sydney.

Family 9. Bladder Flies.

ACROCERIDAE.

These are very curious looking flies with such very small round heads, that at first sight one would think that they were broken off; but on closer examination the little knobs in front will be found to consist of two large eyes joining together on the inner edge, with small, 2 or 3 jointed antennae. Nothing is known about the larval habits of our species, but in Europe they are parasitic on spiders or their cocoons.

The members of the Genus _Pterodontia_ have the body inflated like a bladder; we have several species in Australia, generally found resting on twigs or tree trunks. _Pterodontia mellii_ measures under ½ an inch in length; the thorax and body are swollen out like a bladder; it is of a general black colour, with a mark on the back, the fore legs, and a large blotch on either side of the body bright ochreous yellow; but the dark portions are thickly clothed with fine black downy hairs like a bumble bee. The wings on account of the swollen body look much smaller than they really are. I have specimens from Queensland, and Hunter River N.S.W., and they probably have a wide range.

_Panops flavipes_ is a very curious looking fly from Moruya, N.S. Wales, measuring over ½ an inch in length; it is of a general dark bronzy black tint thickly clothed with fine down, silvery on the tip of the abdomen. The head is very small, black and shining, with the thickened cylindrical antennae standing out in front; the thorax, swollen out behind the head, has a large angular white patch on either side; the abdomen not quite as thick as the thorax is deeply corrugated. The wings have the front half deeply clouded and the hind portion transparent.

_Acrodes fumatus_ is a much smaller species about ⅕ of an inch in length; the head and thorax are black; the bladder shaped abdomen is tawny yellow, with parallel stripes of black down the centre and sides, and transverse white bars at the apex of each segment. They were collected in numbers about Cook’s River, near Sydney.

Family 10. Mydas Flies.

MYDAIDAE.

These might be called “mimic flies,” because, with their large thickened antennae (often swollen out into a compressed club at the tips), their broad heads, elongated bodies, and bright variegated black and yellow markings, they can be very easily mistaken at first sight for Pompilid wasps. The mimicry is further emphasised by the thickened spined legs, and coloured wings.

We have a number of species in Australia; they are allied to the “Robber-flies” which some of them resemble. The larvae of foreign species are predaceous, feeding upon the grubs of various wood-boring beetles.

_Mydas fulvipennis_ has the greater part of the head, thorax, under surface of the abdomen, and thighs black; with the face, antennae, legs, wings and rest of the abdomen except two indistinct narrow bars, bright reddish yellow. It measures over ¾ of an inch in length, and is of the usual elongate robust form with long clubbed antennae and thickened legs. My specimens come from Southern Queensland.

[Illustration: Plate XXVIII.--DIPTERA.

Family MUSCIDAE.

1. _Chaetogaster violacea_ (Macq.).

Family TABANIDAE.

2. _Pangonia guttata_ (Donov.). 6. _Pangonia auriflus_ (Donov.). 14. _Tabanus abstersus_ (Walk.). 7. _Lamprogaster laeta_ (Guérin).

Family ASILIDAE.

3. _Asilis grandis_ (Macq.). 8. _Craspedia coriaria_ (Wied.). 12. _Phellus glaucus_ (Walk.). 13. _Blepharotes splendissima_ (Wied.).

Family DIOPSIDAE.

4. _Zygotricha sp._

Family BOMBYLIDAE.

5. _Comptosia albo-fasciata_ (Thomp.). 11. _Trichophthalma eques_ (Sch.).

Family DEXIIDAE.

9. _Rutilia decora_ (Guérin). 10. _Amphibolia fulvipes_ (Guérin).

(Original photo. Burton.)]

[Illustration: _Plate XXVIII.--DIPTERA._]

Family 11. Robber-flies.

ASILIDAE.

This group is well represented in Australia by some very large handsome robber-flies which attack and kill many insects larger than themselves, transfixing them with their horny bayonet-like proboscis. The large projecting eyes forming the greater part of the head are well separated from the thorax; the three jointed antennae stand out at an angle from each other; the legs are long, stout, and covered with stiff hairs well adapted for holding their prey; they have more or less clouded wings; and a slender, rather cylindrical body tapers to a blunt tip in the female, but in the male terminates in a pair of pincer-like processes. It is an extensive family, over 3,000 species being described from all parts of the world; they are very numerous in America, where one is a very serious pest to honey bees. Their larvae live in the ground and are predaceous, feeding upon the larvae of other insects, particularly those of beetles.

The members of the Genus _Dasypogon_ are small delicate flies that cling to grass stalks, and are easily taken with a sweeping net; they have the typical form of the family, and their slender bodies taper to a point. _Laphria diversipes_ is a common insect about Sydney often taken on fences; it is slightly over ½ an inch in length; its general colour is black, with stout reddish brown legs variegated with black. The head is clothed with stiff grey hairs, the upper surface mottled with golden pubescence, and scattered black hairs. _Laphria rufifemorata_ is a somewhat large insect from Queensland, with the abdomen of a deep metallic blue. _Leptogaster geniculatus_ is a remarkably slender bodied fly, about the same length, found about the Blue Mountains N.S.W. The head is short but wide across; the thorax is oval, and the linear abdomen swells out slightly to the apex; the legs are long and slender, the hind pair with the thighs swollen in the centre. The general colour is shining black with the legs marked with white.

The typical Genus _Asilis_ contains some handsome flies generally met with in open forest country: _Asilis inglorius_, over 1 inch in length, has large black eyes; the front of the head is clothed with grey bristles; the thorax is olive green, marbled with grey pubescence, thickest on the ventral surface; the legs are red, the tarsi black; and the wings are clouded with yellow; the abdomen is much elongated to the pointed tip, reddish brown, the first 3 segments thickly clothed with long, pale, golden, downy hairs, and with the terminal segments covered with very short reddish brown hairs. _A. plicatus_ is slightly larger, of a general greyish brown tint, with pale reddish brown markings on the thorax; the legs are darker brown; the abdomen is lightly clothed with fine scattered grey hairs. _A. fulvitarsus_ is a much smaller species of a somewhat uniform buff tint, inclined to a golden tint on the lower portion of the abdomen; the face is clothed with grey and buff hairs, and the wings are light brown.

_Blepharotes splendidissma_ is a very handsome fly with the abdomen flattened, broad, and almost heart shaped; it measures nearly 1½ inches in length, and 2½ across the outspread wings. It is of a general black colour with the abdomen of a shining bronzy green tint; the face is clothed with yellow bristles; the thorax has grey pubescence on the sides, and the outer margins and tip of abdomen are fringed with tufts of yellow and black downy hairs. I have frequently captured it flying about in the Botanic Gardens, Sydney, in the early summer. _Phellus glaucus_ is a very curious fly found in the interior of Western Australia; it measures nearly 2 inches from the front of the head to the tip of the wings; a great tuft of bright yellow hairs stand out in front of the head; it is thickly clothed on the under-surface of the head with pale yellow hairs; the legs are very stout and hairy, and clothed with black down marked with white and large yellow tufts on the hind legs. The abdomen is thickened, elongated and broadly rounded to the tip, of a uniform deep metallic blue tint, but so thickly clothed with short black down that its rich colour is somewhat obscured. _Craspedia coriaria_ is one of our largest robber-flies, widely distributed all over the interior of the continent; its mouth is produced into a stout pointed awl-like process, with which it can pierce the integument of the stoutest insect, and it can be often seen flying along with its beak buried in the back of a large cockchafer beetle (_Anoplognathus_), and with its large legs clasping its victim as it sucks up its blood. Its general colour is black, with the broad, flattened, more elongate abdomen thickly clothed with short brick-red hairs; the legs and under surface are very hairy, with tufts of stiff black hairs fringing the outer edges of the abdominal segments. The wings are opaque and almost black, with an expanse of about 3 inches.

_Saropogon princeps_, described by Macquart, has a large reddish brown wasp-like form that at first sight might be easily mistaken for a Pompilid wasp. It measures 1½ inches in length, with a wing expanse of about 3 inches. The head, under-surface, centre of the thorax above, the basal segment, and two bands on the abdomen are black; the rest is dull red, with the hind margin of the wings hyaline. I have a specimen from Mittagong N.S. Wales. _Brachyrhopala ruficornis_ comes from Mackay, Queensland, and has a very wasp-like appearance both in the colouration and shape of the body. It is under ½ an inch in length with the typical robber-fly head and spiny legs, but the abdomen is contracted into a cylindrical waist behind the thorax, rounded in the centre, and tapered to the tip. The head and thorax are almost black; the hind margin of the latter and legs are dull red; the abdomen is dull yellow with the basal segments marked with blackish brown, forming two almost confluent bands round the broad centre.

Family 12. False Robber-flies.

APIOCERIDAE.

These flies are of medium size not unlike _Muscidae_, with large elongated bodies, short antennae, and clear wings. This is a small family containing two genera, the species of which are peculiar to North America, Chili, and Australia.

_Apiocera bigotii_, described by Macquart, is about ¾ of an inch in length; it has a short head not so wide as the thorax, with a long projecting proboscis; the elongate broadly rounded thorax is truncated behind; the abdomen is broadest in front, rounded, and tapers to the tip, which terminates in a tuft of fine spines. The wings are somewhat iridescent with reddish veins; the general colour of the fly is a dull brown, with white hairs and silvery pubescence clothing the hind portion of the head and under-surface of the thorax, and also mottling the dorsal surface of the body with grey. Some specimens in my possession come from the Shoalhaven district. _Apiocera asilica_ described by Westwood is a larger much darker insect, with black hairs on the upper surface and grey on the under surface; it ranges from Queensland to the Blue Mountains N.S.W.

Family 13. Big-eyed Flies.

PIPUNCULIDAE.

These are tiny little creatures with very large heads consisting almost entirely of two great hemispherical eyes. The short antenna terminates in a bristle.

About 80 species had been described, chiefly from Europe, until Perkins published the descriptions of 26 species from Australia (Leaf Hoppers and their natural enemies Pt. iv. Pipunculidae) Hawaii 1905.

They are remarkable for their habits in the larval state, being parasitic upon the larvae and pupae of frog-hoppers, chiefly Jassidae,

## particularly those Homoptera that have the tip of the abdomen clothed

with waxy filaments. When full grown the dipterous larvae leave their host and bury themselves in the soil, where they pupate. Mr. Koebele allowed me to examine the collection he made of these little flies before they were described by Mr. Perkins. Many of these he reared from infested frog-hoppers in Queensland when studying sugar-cane pests.

_Pipunculus helluo_ was observed swarming round the larvae of _Siphanta_, which were abundant on fig trees near Bundaberg Queensland; this species was also taken by Koebele near Sydney. _P. cinerascens_ is remarkable in the larval form, as it does not fall to the ground and pupate in the soil, but forms its puparium upon the surface of the living leaves in the open. _P. cruciator_ comes from the district of Cairns, N. Queensland.

Family 14. Hover Flies.

SYRPHIDAE.

Several species are well known and common in gardens, where they are popularly known under the name of “Bee” or “Hover Flies” from a way they have of poising, apparently motionless, over flowers and aphid-infested bushes, for the movement of their wings is so rapid as scarcely to be detected. The perfect flies, which among the carnivorous species have slender bodies more or less barred or banded with yellow, lay their eggs upon aphis-infested plants; the young larvae emerging from the white eggs feed exclusively upon aphids and plant lice; the full-grown larva is legless, very elongate in form, and has great powers for extending and contracting its abdominal segments, so that the body, from a rounded mass, can extend into a long and slender form. The full-grown larva pupates in an oval hard chrysalid which usually falls to the ground.

The typical Genus _Syrphus_ is well represented in Australia by several fine species, all of which are aphid eaters, and fly about in the bright sunshine but shelter among the foliage at other times; whenever aphis appear the syrphid flies soon follow, and I have seen them round the aphid-infested briar bushes in countless thousands. _Syrphus pusillus_, figured in the Agricultural Gazette N.S.W. 1904 under the name of _Syrphus viridiceps_, is our commonest species found upon aphis-infested rose bushes, orchard trees, and wheat fields. It measures about ⅓ of an inch in length; has large reddish eyes, yellow face, and dull metallic green thorax with yellow scutellum; the darker abdomen is banded with three interrupted transverse yellow bands, and smaller marks on the apical segments. _S. viridiceps_ is a more slender form, with a green face; the whole of the thorax is shining lead colour, with fine yellow bands on the abdomen; the legs are dark, and the whole fly is lightly clothed with fine hairs. Both these species may be taken on the same bush, and both have a very wide range over Australia.

[Illustration: =Fig. 146.=--_Syrphus viridiceps_ (Macquart).

A common Hover-fly that destroys rose and peach aphis.

(“Agricultural Gazette,” N.S.W.)]

The Drone or Bee Fly, _Eristalis tenax_, is another common garden fly with a very wide range, and is an introduced European species. It measures over ½ an inch in length and is broad in proportion; the head and thorax are clothed with yellowish brown down, and the smooth shining abdomen is mottled with black and brown. The larvae are dirty white maggots with slender rat-tails at the tip of the body, and they live in all kinds of rotten or semi-liquid refuse.

_Helophilus bengalensis_ is a smaller, robust fly with rounded eyes; the thorax is richly barred with parallel grey lines on the dorsal surface; and there are two large lunate yellow spots at the basal portion of the abdomen. The lower part of the abdomen tapers to a rounded tip and is clothed with yellow down. This fly was originally described from Bengal by Wiedemann; Schiner has reported it from Batavia; my specimens come from Queensland. _H. griseus_ was described and its life history given in my “Entomology of the Grass-trees” (Pro. Linn. Soc. N.S.W. 1896) under the name of _Orthoprosopa nigra_. The larvae, elongate in form, with a short anal tubular tail, swarm in great numbers between the outer shell and the caudex of the dead rotting trunk of the grass-trees among the slime and water. They pupate in the damp earth in captivity, forming a light brown oval case with the remains of the larval tail shortened and retracted. This handsome black fly, over ½ an inch in length, has the face and antennae bright yellow; the dorsal surface clothed with fine black pubescence; the scutellum smooth and shining; the sides fringed with scattered grey hairs; and the wings clouded. There is a second species found in similar situations; the larvae have the typical slender rat-tails, and when they pupate transform the tail into a curved tubular process at the extremity of the chrysalis.

[Illustration: =Fig. 147.=--_Eristalis tenax_ (Linn.).

The Drone or Bee-fly; usually found upon flowers.

(“Agricultural Gazette,” N.S.W.)]

_Sphiximorpha australis_, from Southern Queensland, is a very curious broad thickset black and yellow fly, with spatulate tipped antennae standing out in front of the two large eyes; the head is slightly larger than the thorax, which is stout and thickened; and the broad abdomen is rounded at the extremity. The general colour is black, with the face, three spots on the sides of the thorax, scutellum, apical portion of legs, and two bands on the abdomen rich yellow. The wings are clear, except a dark stripe along the front margin. This curious fly has a striking resemblance to some of the yellow banded mud-nest wasps (_Odynerus_ and _Alastor_), but the reason for their bright colouration and abnormal shape is at present unknown.

Family 15. Wasp-flies.

CONOPIDAE.

These are handsome flies of moderate size, many of which are very wasp-like in the shape of the abdomen and in general colouration; they have the proboscis prolonged but usually drawn up and hidden; the 3-jointed antennae inserted in front of the head are close together at the base, with the first joint very short. Comstock says that the larva of _Conops_ is a soft whitish 11-jointed flask-shaped grub, with a long neck and mouth armed with lips and hooks (mandibles) and two lateral elevated plates supporting the two spiracles. It was found by Lachat and Audouin living in the body of a _Bombus_. Most of the members of this family are found as parasites upon different bees and wasps; the flies deposit their eggs upon the perfect insects; the larva bores into the abdomen, feeds upon the contents, and finally pupates in the shell of the body. They are considered by most writers to be allied to the _Syrphidae_.

This is a small family in regard to numbers of species, but they are widely distributed: Van der Wulp lists 14 species of the Genus _Conops_ from South Asia, including the Malay Archipelago (Cat. Described Diptera 1896), and others have since been described.

_Conops pica_, described by Macquart from Australia, is found in the Mittagong district, N.S.W. It is slightly over ¼ of an inch in length; has large lance-tipped antennae standing out in front; a large head; the abdomen very slender at the base swelling out to a broadly rounded tip, giving it a striking resemblance to the small “mud-nest wasps.” This resemblance is further borne out by its general dark brown colour marked and banded with yellow, which upon the abdomen forms two broad bands, a spot on the sides, and a large rounded blotch on the extreme tip; the legs are banded, and the wings are striped in front with brown.

Family 16. Fruit Flies, Leaf Mining Flies, &c.

MUSCIDAE ACALYPTRATA.

Under this heading Sharp places a large division of closely related flies comprising 29 families, which he treats in a very brief manner; we have a large number of interesting species in some of these families that are worthy of notice, for some of them are very serious pests to the gardener and orchardist. Sharp says: “Taken collectively, they may be defined as small flies with 3-jointed antennae (frequently looking as if only 2-jointed) bearing a bristle that is not terminally placed; frequently either destitute of squamae or hairy, these imperfectly developed so as not to cover the halteres; and possessing a comparatively simple system of neuration, the chief nervures being straight, so that consequently few cells are formed.”

The DIOPSIDAE comprise in the typical Genus _Diopsis_ some very curious looking flies, rather slender in form, with narrow wings, and the sides of the head produced into an elongate stalk, at the tip of which is placed the rounded eye, reminding one of the stalk-eyed crabs. Westwood monographed this genus in the Transactions of the Linnean Society 1835, where he figured and described 21 species from Africa, India and Java. I have two very fine species from North Queensland, belonging to the Genus _Zygotricha_, and a number of allied forms placed in the Genus _Achias_ by Van der Wulp (Catalogue of the Described Diptera from South Asia 1896) recorded from New Guinea. The Stalk-eyed fly, _Zygotricha sp._, measures nearly ½ an inch in length, with the eyes measuring over ¼ of an inch from tip to tip; its general colour is yellowish brown, the face bright yellow; eyes black; thorax finely striped with grey; wings mottled; the curious angulated abdomen shining with metallic tints, and tipped with stout hairs.

The cosmopolitan “Skipper” in cheese, is the larva of _Piophila casei_; it pupates in a slender dark chrysalid; the small slender dark fly swarms round over-ripe cheese, fat, and other dried foods.

The little “Fruit Flies” belonging to the DROSOPHILIDAE, sometimes also known as “wine flies” from their habit of swarming round the freshly-filled wine casks, lay their eggs in decaying vegetable matter; they are often attracted to over-ripe fruit, and by their presence sometimes cause it to decay; they are common all over the world. The maggots sometimes found among pickles in vinegar and brine belong to flies of this group. _Drosophila obscura_, a tiny light brown fly with a dark coloured head, breeds in damaged tomatoes.

[Illustration: =Fig. 148.=--_Dacus (Tephritis) tryoni_ (Froggatt). The Queensland Fruit Fly.

1. Showing the jaws of the larva; 2. adult fly enlarged; 3. larva; 4. chrysalid; 5. tip of the abdomen showing the breathing orifices; 6. fly natural size.]

The TRYPETIDAE comprise the true “fruit flies,” many of them very handsome little creatures; some of them form regular galls in the twigs of plants; others with their needle-like ovipositors puncture the ripening fruit, depositing their eggs beneath the skin; the maggots cause the fruit to rot, often before it can be gathered, and thus do a great deal of damage in Australian orchards. The Queensland Fruit-fly, _Dacus (Tephritis) tryoni_, ranges from Queensland (where it probably originally infested native bush fruits) into N.S. Wales, and is now a serious orchard pest in both States. It is a dull brown insect marked with yellow, about the size of a large house fly, with a rather wasp-shaped body, and large transparent wings. I have described several other allied species coming into Australia from the Islands in damaged fruit, “Notes on Fruit-maggot Flies with Descriptions of New Species” (Agr. Gazette N.S. Wales 1899). _Dacus (Tephritis) psidii_ was bred out of guavas imported from New Caledonia; it is about ¼ of an inch in length; is dull yellow, with the thorax distinctly striped, and the abdomen black; the transparent wings are thickly mottled with brown. Tryon says that it is a common fruit-fly pest in Queensland, damaging bananas and other fruits. _Trypeta musae_ was obtained from bananas brought from the New Hebrides: it is a slightly larger fly, with the head and thorax dull yellow; it has no distinct dorsal stripe on the thorax, and the wings are very thickly mottled. _T. bicolor_ is a larger native species with reddish brown head and thorax; with black body; with beautifully mottled black wings having the base and sides unclouded. I have taken it on the trunks of wattle trees near Bathurst, N.S. Wales. The “Mediterranean Fruit Fly,” _Ceratitis (Halterophora) capitata_, first recorded from oranges brought from the Azores to London, was described by Macleay in 1826; it has a wide range, and was introduced into New South Wales some years ago; it is now one of the most serious pests that orchardists have to fight. It is a smaller more thickset fly than the Queensland pest, with the thorax dark metallic brown, and the wings richly variegated. The male is remarkable in having a pair of spatulate hairs, like a second pair of antennae, springing out in front between the eyes. _Trypeta poenia_ is a tiny little fly with a grey pubescence over the thorax and abdomen; the thorax is finely mottled, and the delicate wings are very finely but thickly marked with dark brown; I have taken this species when beating the low scrub in the western country round Condobolin, N.S. Wales. _Lonchaea splendida_ is a very brilliant metallic green fly with pale smoky wings; it is smaller than a house fly, with a much more elongated body; its larvae infest decaying tomatoes, potatoes, egg-fruit and other solanums; it has a wide range from the Pacific Islands and New Zealand, over Australia.

The family ORTALIDAE is represented here by a very handsome species, _Ortalis coerulea_; it is about the size of a house fly, with deep metallic blue thorax and banded black abdomen; the transparent wing is clouded with black at the base and the tip, and has a black V-shaped band in the centre. It is very common in summer usually resting on the foliage of the grass-trees, and can be easily captured with a net. _Lamprogaster laeta_ is another fine species, with a wide range from Victoria to Queensland. It measures nearly ½ an inch from the front of the head to the tip of the body; the large semitransparent wings are blotched along the front with black. The dorsal surface and curious angular abdomen are deep metallic blue; the legs and under-surface reddish brown. I have usually found it on the highlands, and it is common on the Blue Mountains N.S.W. in the summer months.

The AGROMYZIDAE are small yellow flies, sometimes marked with green; they puncture the tissue of plants and cause excrescences and galls upon the foliage and flower buds. One tiny species, _Agromyza sp._, attacks the midrib of the leaves of the “Blood-wood” (_Eucalyptus corymbosa_), common about Sydney; producing soft yellow spongy excrescences aborting all the young foliage. _A. phaseoli_ is a great pest to the growers of french beans in the Gosford district N.S.W.; the fly inserts her eggs in the stem of the young plant just above the surface of the ground. It is a tiny black fly, with bluish tints on the body. It was described by Coquillett (Pro. Linn. Soc. N.S.W. 1899) from specimens I sent to him for identification.

[Illustration: =Fig. 149.=--_Agromyza phaseoli_ (Coquillett).

The French-bean fly, the larva of which feeds on the stems.

(“Agricultural Gazette,” N.S.W.)]

[Illustration: =Fig. 150.=--_Phytomyza affinis_ (Fallen).

An introduced Leaf-mining fly, and a common garden pest.

(“Agricultural Gazette,” N.S.W.)]

The PHYTOMYZIDAE are small dark coloured flies, whose larvae are leaf miners; and several species are well known pests to the gardener. _Phytomyza affinis_ breeds in the winter in the leaves of the sow thistle; the next generation swarm on the marguerites, sunflowers and many others of the _Compositae_, thereby causing them to wither and fall.

The SAPROMYZIDAE contain a great number of small flies which are generally met with resting among the foliage when sweeping or beating the scrub in the early morning. They seldom have the wings spotted, and the abdomen is broader than that of the former group. The larvae feed under the bark of trees, or among decaying vegetation. _Sapromyza fuscicornis_ is of a uniform pale brownish yellow, with dark eyes, and with scattered stout bristles on the thorax; it is a large species over ¼ of an inch in length to the tip of the closed wings. It has a wide range over Australia. _S. decora_ is a very much smaller dark brown fly, with a fine white stripe on each side of the thorax extending across the sides of the head above the eyes. It is common in summer in the orchards among the orange trees.

In the members of the Genus _Celyphus_ the scutellum is so abnormally inflated that it covers all the posterior parts of the body, so that these tiny shining black creatures are quite unlike the typical Diptera. A dark brown fly about the size of a house fly that has been described under the name of _Batrachomyia nigritarsis_ by Skuse, is a parasite in the larval state on the back of several of our common frogs, where feeding under the skin it forms a regular blister; when full grown the larva makes its way through the skin, and pupates in the damp soil.

The SCATOPHAGIDAE are slender, elongate, medium sized flies that can be bred out of dung or decaying vegetable matter, and are found in most parts of the world. _Scatophaga guerini_ measures over ⅓ of an inch in length; it is of a dull greyish brown tint, marked on the head and thorax with parallel whitish bars, thickly clothed on the stout legs with fine hairs; and the long wings are folded over the back when at rest. It has a wide range; I have it from Sydney, and have bred it from the cylindrical white maggots in “toad-stools” collected on the banks of the Darling River, N.S. Wales.

The Genus _Nerius_ (placed by Van der Wulp in the Sub-family CALOBATINAE, following the SCIOMYZINAE) is represented by two fine species common in North Queensland. They are very slender, long-legged flies, with long, straight-veined wings, rounded at the extremities, and folded over the narrow pointed abdomen; the head, which has a distinct neck, might be described as pear-shaped, with short, stout, lance-shaped antennae standing out in front, and elongate flattened eyes with a dorsal depression between them; the abdomen is elongate, oval; and both species, about the same size, measure ½ an inch in length. _Nerius inermis_, “the Banana-stalk Fly,” is of a uniform dull brown colour, with the dorsal surface of the head and thorax striped with white, and the whole of the under surface and thighs (except a brown comma-like mark on the sides) white. The slender white maggots feed in the ends of the decaying stalks of the bunches of Queensland bananas, forming elongate reddish brown chrysalids when they pupate; they are easily bred out in captivity. This species was originally described from the Nicobar Islands by Schiner; and has also been recorded from Celebes and Aroe. _N. lineolatus_, described by Wiedemann from Java, is common in North Queensland; it differs from the last species in having the dorsal surface more thickly and brightly striped with white, and the legs being barred with white.

Family 17. Anthomyia Flies.

ANTHOMYIDAE.

In general appearance they are very like the house fly, of small size and indefinite colour; they differ in the structure of the wings, and the eyes of the male are generally large and in contact; the antennae are bare or feathered. In their larval habits they vary very much: some are simply scavengers; others feed on living vegetation, and like the onion and cabbage flies are serious pests; and a few are parasitic. The family is a large one, and species are found in most parts of the world.

The common bluish fly resting on the decaying weed, and flying along in front when one is walking along the sea shore, belongs to the Genus _Lispe_; it looks like a house fly with longish legs and a pale tint.

_Ophyra analis_ is a very common inland fly, and may be found swarming round dead sheep, or bred from pupae found under carrion lying in the bush. It is a shining blue black fly about the size of an ordinary house fly, and is lightly clothed with bristles on the sides of the thorax; it has a somewhat heart-shaped body, and clear wings. A second species, _O. nigra_, originally described by Wiedemann from China, is found in Australia, and is also recorded by Walker from the East Indies. It may be found swarming about dead sheep in summer. _Phoania personata_ might be taken for a large house fly from the regular stripes on the thorax, but it is more thickly clothed with bristles, and the abdomen has a deep metallic blue tint. I have bred numbers from larvae pupating in rotting oranges piled on the ground. _Limnophora ruficoxis_ is a somewhat smaller fly with the dorsal surface of the thorax and abdomen clothed with a dull buff pubescence; and the scutellum is smooth and shining. I have specimens from Sydney, N.S.W., and Gatton, Queensland.

Family 18. Parasite Flies.

TACHINIDAE.

This is one of the most useful groups of flies to the agriculturist, for nearly all the members deposit their eggs upon the living larvae of other insects such as the plant-destroying cut-worms, many different moths, and the grubs of our large saw-flies, and immature grasshoppers. This is a family of considerable extent, for over 1,000 species have been described from America alone, and in Van der Wulp’s Catalogue 187 species are listed from South Asia, but very little has been done in working up the Australian species.

In general appearance they are not unlike large house flies, but more bristly; the bristle of the third antennal joint is bare; the posterior cell of the wing almost or quite closed, and the large squamae cover the halteres. They attach their white eggs to the surface of the caterpillar with a gummy secretion, and it is quite common in summer time to find caterpillars thus infested, the perfect flies generally emerging from the pupal shell of their victim.

The members of the Genus _Winthemia_ are rather large flies, parasitic upon the larvae of different moths; several American species are great checks upon the increase of the “Army worm” (_Leucania unipuncta_). _Winthemia lata_ measures slightly under ½ an inch in length, and is thickset in proportion; it has a silvery face, with the brownish thorax covered with short stout bristles on the sides; the abdomen is black, with the sides and outer margin of the segments blotched with dull yellow; and the whole upper surface is lightly clothed with fine bristles. I have bred this fly from our Native Silkworm Moth (_Antheroea eucalypti_), from Lewin’s Moth (_Ocinaria lewinae_), and from an undetermined hawkmoth.

The Genus _Miltogramma_ comprises a number of smaller flies common in Europe, which lay their eggs upon the captured prey of the sand wasps while the latter are placing them in their burrows in the ground; and not only does the parasitic fly larva devour the food supply, but also when that is finished, feeds on the baby wasp. An Indian species is parasitic upon one of the large plague locusts. I have a very handsome undetermined species from Southern Queensland which has the abdomen ringed with bright yellow bands; this would suggest that it may deposit its eggs in the underground chambers of a similarly banded _Bembex_. Another much smaller species, not unlike the house fly in size and general colouration, has the grey abdomen barred with black.

Family 19. Metallic Green Flies.

DEXIIDAE.

These flies differ from the Tachinidae, which they otherwise resemble, in having longer legs, and the bristle of the antennae pubescent or plumose. Australia is rich in large handsome species, often brightly marked with metallic tints; they are usually most plentiful in open forest country, often resting on tree trunks; when flying round they make a loud humming sound. Most of them are parasitic in their habits, depositing their eggs upon the larvae of lamellicorn beetles that are buried in the ground.

_Chaetogaster violacea_ is of the usual thickset form, with a broad body and long pointed wings; it measures nearly 1 inch from the front of the head to the tips of the folded wings. It is of a general dark metallic blue colour, with the dorsal surface of the head and thorax marked with grey, and the whole insect is clothed with scattered black bristles. The wings are clouded with dull yellow on the basal half, giving it a very distinctive appearance. _Amphibolia fulvipes_ is another very handsome and smaller fly with a broader body than the last, but the wings are shorter and clouded at the base; the head and legs are yellow; the rest black, with the thorax spotted behind and marked with a row of short broken parallel bars in front; the greater part of the abdomen above and below is creamy white mottled with seven bilobed blotches of black forming a pattern on the dorsal surface. It is found about Sydney and has a wide range on the eastern coast.

_Amenia leonina_ is about ½ an inch in length with a more rounded abdomen. The large head is bright yellow, with the thorax and abdomen rich metallic blue; the sides of the thorax and abdomen are marked with several white circular dots, the last two on the tip of the abdomen very distinct. It is found in Tasmania, and ranges along the eastern coast of the mainland into Queensland.

The typical Genus _Rutilia_ is well represented in Australia by a number of large, showy flies rich in metallic tints, and as a general rule not so thickly or coarsely clothed with bristles. _Rutilia formosa_, originally described from New Holland by Desvoidy, is not uncommon along the eastern coast in the summer months. It measures from ¾ to 1 inch in length; is of a general rich light metallic blue tint; the abdomen indistinctly barred with black is rich metallic coppery red, duller in the larger females, which have the abdominal segments more hirsute and bristly. The larvae are parasitic upon beetle grubs, probably those of the brown cockchafer (_Anoplognathus_). _R. decora_ is about the same size and has much the same habits and range. The thorax is rich metallic blue, darker in front, with a row of short black bars; the abdomen is black with a double row of bright green metallic spots down the centre, the two at the anal tip largest. _R. vivipara_ measures about 1 inch in length, with a wing expanse of 1½ inches; it is of a general dull greyish brown tint; the abdomen is lighter brown, and has a dark line down the centre and the sides and tips lightly clothed with grey hairs. _R. inornata_, about the same size as the last species, is a much darker fly; the abdomen is of a uniform dull shining black with grey hairs on the sides but none on the tip. Both these species have an extended range in forest country.

_Myocera longipes_ has the general colouration of a house fly, with long, clear wings behind which are large white squamae; and it has very long slender legs. It has a curious habit of resting on the tree trunks with its long legs spread out in a very characteristic manner.

[Illustration: Plate XXIX.--DIPTERA.

Family MUSCIDAE.

1. _Lucilia tasmaniensis_ (Macquart). Large blue-bottle fly. 2. _Lucilia caesar_ (Linn.). Introduced sheep fly. 3. _Lucilia sericata_ (Meigen). Metallic blue-bottle fly. 4. _Musca domestica_ (Linn.). Common house fly. 5. _Musca corvina_ (Fabr.). Bush fly.]

[Illustration: _Plate XXIX.--DIPTERA._]

Family 20. Flesh Flies.

SARCOPHAGIDAE.

These flies differ from the true house flies in having the bristle of the antennae plumose at the base but fine and hair-like at the extremity. They lay their eggs or living larvae upon meat or other exposed food, and are also known as “Scavenger” flies because they frequent evil-smelling places like pig-sties and slaughter-yards. Some species are known to deposit their larvae in the nostrils of animals, and there are several records of the death of human beings from infestation by these maggots.

The typical Genus _Sarcophaga_ is world-wide in its distribution, and contains a number of well known species. _Sarcophaga aurifrons_ is our commonest species in Australia, and is also found in the Malay Archipelago. It is over ⅓ of an inch in length; the front of the head is golden; the large eyes deep red; the legs black; and the thorax and abdomen black but thickly clothed with silvery grey pubescence; the black shows through, forming three black bands on the front of the thorax; and the abdomen is mottled with indistinct spots. _S. frontalis_ is a slightly larger species with the face very bright golden yellow; the black bars on the thorax finer and darker; and the abdomen mottled with a more irregular pattern. A much smaller species, hardly larger than a house fly, was described by Skuse (Agricultural Gazette N.S.W. 1891, p. 251) as a parasite of the plague locust; he named it _Masicera pachytyli_; this fly Mr. Coquillett says belongs to the Genus _Sarcophaga_. I have since bred a much larger species from the bodies of locusts in the Bombala district, N.S.W. _Tachina oedipoda_, described by Olliff (Agr. Gaz. N.S.W. 1891, p. 769), I am also informed by Mr. Coquillett, should be _Sarcophaga oedipoda_, and is closely allied to _S. aurifrons_: it also is a parasite on the same species of locust.

Family 21. House Flies.

MUSCIDAE.

This group comprises all the typical house flies, some of which are world-wide in their distribution. All of them have the bristle that forms the tip of the antennae hairy or plumose, while the abdomen is spineless, without bristles except at the extremity.

They deposit their eggs in stable manure or other decaying matter; the maggots, developing very rapidly in warm weather, form the usual hard parchment-like chrysalids from which the perfect flies emerge. Many interesting observations have been lately made on the habits of house flies and the danger of their spreading diseases by carrying germs or

## particles of putrid matter upon their feet, and thus contaminating

food or transferring germs into open wounds; it was proved in the Spanish-American war that the swarms of flies had a great deal to do with the spread of fever in this manner. _Musca domestica_, the common house fly, is almost world-wide in its distribution, and is the chief species found inside the house. In the larval state it chiefly develops in stable manure. It measures about ¼ of an inch in length; is of a uniform black tint but is so thickly clothed with grey tomentum that it appears to be brown; the eyes are red; the thorax is clothed with stiff black bristles, and has four parallel bars down the centre of the dorsal surface. The freshly deposited eggs hatch within a day or two; the maggots develop within six days, and remain in the pupal state for only a few days in the summer; so that it is no wonder that they multiply with such marvellous rapidity, particularly when we discover that one house fly will lay over 1,000 eggs in the season. _Musca corvina_ is a smaller darker tinted species, showing only two parallel stripes down the thorax. It is a common bush species and a great pest in the bush all through the summer, swarming in countless thousands from the eastern coast into the interior. It has a wide range over Europe, North America, Ceylon, and the Malay Archipelago. _Stomoxys calcitrans_ is of a more brownish tint, with the abdomen more flattened, and it differs from the last two species in having a well developed biting mouth; this fly is a troublesome pest to horses, and will alight on one’s hand and bite quite sharply. It has a wide range from Europe across Asia to Ceylon, Java, and Australia.

The Genus _Calliphora_ is well represented by several very distinct species of typical “Blow-flies”; but though the common European species, _Calliphora vomitaria_, is said to be common in New Zealand I have never taken it in Australia. _C. villosa_ is our large common blow-fly; it measures about ½ an inch in length; is of a general slate grey colour with the abdomen thickly clothed with fine golden pubescence giving it a bright mottled yellow tint. _C. oceaniae_ is the smaller blow-fly with a steely blue abdomen, the base on either side bearing a dull yellow blotch by which it can be easily distinguished. Both these species are found in the bush and in the house; they lay their eggs on any food they can gain access to; but in the summer, or when they cannot get at food in time, the egg is hatched in the body of the mother and dropped as a living maggot. Some of the bright metallic species also come in this Genus; _C. rufifaces_ is a much smaller bright rich metallic blue fly, with a silvery face, red eyes, and white flaps behind the wings; it, and the much smaller _C. varipes_ with a yellow face and darker tinted body, are common about dead sheep or decaying matter in the interior.

[Illustration: Plate XXX.--DIPTERA.

Family MUSCIDAE.

1. _Calliphora oceaniae_ (Desv.). Blue-bodied blow-fly. 2. _Calliphora oceaniae_ (Desv.). Maggot. 3. Head segment of maggot, showing mouth hooks. 4. Anal segment of maggot, showing tubercles. 5. Pupa. 6. _Calliphora villosa_ (Desv.). Yellow blow-fly.]

[Illustration: _Plate XXX.--DIPTERA._]

_Neocalliphora ochracea_ is somewhat thicker and broader than _Calliphora villosa_, and a much rarer species; it is of a general dull reddish brown colour, with the head and thorax darkest.

In the Genus _Lucilia_ we have the typical “Bluebottle” flies, which are well represented in this country: _Lucilia sericata_ and _L. caesar_, both of a moderate size and deep metallic green and coppery tints, are widely distributed. _L. tasmaniensis_ is a larger species, measuring under ½ an inch in length; it is of a uniform bright metallic blue, and has a wide range.

Family 22. Bot-flies.

OESTRIDAE.

The members of this family are well known in most parts of the world in the larval state as “bots,” internal parasites in the stomach of the horse, in the nostrils of sheep, and the skins of cattle. The life history of the common European bot-fly, _Gastrophilus equi_, is well known; the active fly lays her eggs upon the shoulders or jaws of the horse, attaching them to the hair by a gummy secretion; the horse licking itself transfers the eggs into its mouth, where the tiny maggots hatch out and are carried down into the stomach. They are provided with a pair of fine curved hooks in front of the head by which these little creatures hook themselves into the membrane of the stomach, absorbing their nutriment from the liquid with which they are surrounded. When fully developed these oval spiny bots detach themselves and pass out with the excrement, the maggots at once burying themselves in the damp soil and pupating; the perfect fly emerges early in February in most parts of N.S. Wales. The flies, about ½ an inch in length, have large thickset bodies thickly clothed with short brown or golden hairs, giving them the general appearance of a hairy bee; the male has a short rounded abdomen; that of the female is greatly elongated and usually curled up underneath. There are probably several introduced species now common in Australia with a wide range over the country. It is remarkable that though they do not bite or sting the horses when laying their eggs, yet as soon as the horses hear the loud hum of the bot-fly they gallop about and show an inherited fear of this pest, which, though it does not kill them, must be a very unpleasant parasite when numerous. The members of the Genus _Hypoderma_ are a very serious pest in Europe and other countries where they infest cattle, and are known both as “warble” or “bot-flies.” The fly lays her eggs upon the back of the beast; the tiny larva makes its way through the hide, beneath which it lives and feeds upon the putrid matter caused by the irritation of its presence; it finally produces an inflamed blister-like swelling or “warble,” eventually working its way out through the hide and falling to the ground, where it buries itself and pupates. No species have been found in Australia, but in some parts of England very serious damage is caused to the health of the beast, and the skin by being perforated loses value for making leather.

[Illustration: =Fig. 151.=--_Gastrophilus equi_ (Fabr.).

1 and 2, The introduced Bot-fly, showing dorsal and lateral view of female; 3, eggs attached to hairs of horse; 4, egg enlarged (the eggs should be more truncate at the tips); 5, larval bots attached to piece of the stomach of a horse; 6, bot much enlarged; 7, enlarged head of bot showing the mouth hooks.]

The Sheep Nostril Fly, _Oestrus ovis_, has a wide range over the world, and was probably introduced into Australia many years ago, though it has been noticed only quite recently as a serious pest. This fly lays living maggots in the nostril of the unfortunate sheep; the maggots work their way up into the frontal sinuses of the head, where they remain until fully developed, when they turn downward and are usually sneezed out by the sheep in their efforts to get rid of the obstruction. The fly is slightly under ½ an inch in length; the upper surface of the head and body are grey to dull yellow, spotted or mottled with darker tints; the abdomen is yellowish mottled with darker markings. It has been found chiefly in the Blue Mountains N.S.W.

Family 23. Louse or Spider Flies.

HIPPOBOSCIDAE.

These are parasitic Diptera, that having taken to idle and slothful habits (though some of them can fly very well), take up their quarters among the fur or feathers of different animals and birds, where they live and are carried about by their hosts. To suit this method of existence they have become quite altered in structure; they have flat leathery bodies, and their feet are produced into large pincer-like claws which enable them to cling to the skin of their host. Some have large wings with stout nervures but very rudimentary venation; a few though provided with wings at birth bite them off soon after; and others like the well known “sheep tick” are wingless.

As a rule their presence even when numerous does not seem to incommode the infested animals after they have become used to them, for the wild ponies in the New Forest in England are often covered with the horse-fly, _Hippobosca equi_, and they take no notice of them. Yet if one alights upon a horse unaccustomed to the presence of the fly he becomes almost crazy with fright, probably from the pinching or tickling sensation produced by their claws.

[Illustration: =Fig. 152.=--_Ortholfersia macleayi_ (Leach).

A parasitic fly that lives upon wallabies. Figured by me as _Olfersia macleayi_ (Leach) in the “Agricultural Gazette,” N.S.W.]

The Common European Sheep Tick, _Melophagus ovinus_, was introduced at a very early date into this country among the wool on the backs of sheep. It is a dark-brown, wingless creature thickly clothed with fine hairs, more like a stout-legged spider than a fly in general appearance, but it has not the requisite fourth pair of legs. These bristly legs are furnished with the usual stout curved claws, between which is a slender appendage like a short string, supposed to be used to hang on with by coiling it round the wool. From their blood-sucking habits and these pincer-like claws, they are very annoying to the sheep when numerous.

The Wallaby Louse Fly, _Olfersia macleayi_, is very common on small marsupials in Australia and Tasmania. When the dogs while hunting pull down and kill a wallaby, these flies generally crawl off and cling to the dog’s nose, rendering him very unhappy. It is a winged form, measuring under ½ an inch to the tip of the folded wings, and is of a uniform shining dark brown tint with a greenish shade very noticeable in the legs. Speiser (Annals Musei Nationalis Hungarici 1904) has placed this species in his Genus _Ortholfersia_.

_Ornithomyia perfuga_, taken on an owl (probably _Spiloglaux boobook_) near Brisbane, has been recently described by Dr. Speiser: it is a larger species of a more reddish brown colour. A very fine louse fly, also taken in Southern Queensland upon a white hawk, measures nearly ¾ of an inch to the tip of the folded wings, and has been identified by the same gentleman as _Ornithoctona nigricans_, described originally by Leach. Among the few other species described from Australia is one found on our pretty little emu wren, which was described by Schiner in the “Zoology of the Voyage of the Novara 1850” under the name of _Ornithomyia stipituri_. A number of our native birds act as hosts for these curious flies; the fruit pigeons, swallows, fly-catchers, and others are known to have them; and when they are systematically collected our list will probably be a large one.

The NYCTERIBIIDAE are another typical family of louse-flies found upon different bats, which are very small in comparison with the true louse-flies: they are always wingless, and have a world-wide distribution. They are reddish brown creatures covered with stout spines; the head is buried in the thorax; and the legs, very long and slender, terminate in immense pincer-shaped claws. Nearly all our bats are more or less infested with these “spider flies,” and several species have been described. Rainbow has recently described one under the name of _Nycteribia pteropus_ from a flying fox taken at Batavia River, N. Australia (Records Australian Museum 1904).

Family 24. Fleas.

PULICIDAE.

The classification of the fleas has always been a matter of doubt; modern entomologists usually place them at the end of the Diptera, considering them a group of degraded flies that from their parasitic habits have become wingless, and have developed wonderful jumping powers; other specialists who have devoted much attention to the question consider them as worthy to rank in an Order, and follow Latreille, who called them SIPHONAPTERA; other writers, like Taschenberg, who wrote his Monograph entitled “Die Flöhe” in 1880, formed them into distinct families. The latest revision of the family is Baker’s “Revision of American Siphonaptera, &c.” (Smithsonian Institute 1904); in this he gives a list of the described species, placing them in five families, and records a total of 134 species from all parts of the world.

Messrs. Jordan and Rothschild in a “Revision of the Sarcopsyllidae” (University of Liverpool 1906) criticise Baker’s classification, and reduce the families to four, extending the limits of the Family SARCOPSYLLIDAE, and adding seven new species.

The flea differs from most other insects in having the whole wedge-shaped body vertically flattened. It is admirably adapted for crawling through hair or feathers, and the large stout spiny legs are well suited for jumping. The head, indistinctly separated from the body, is short, furnished with jointed antennae situated above but behind the eyes; the mouth is produced into a stout pointed proboscis with which it punctures the skin and sucks up the blood of its host. They are all of a more or less reddish brown tint, clothed with scattered stout bristles, and the abdomen is rounded at the apex; the legs are furnished with a pair of tarsal claws. The fact that fleas are capable of spreading the germs of plague and even leprosy has caused a great deal of attention to be devoted to this group, and they have during the last few years been sought for and collected from all parts of the world.

Two species are common in the house in Australia, of which the “domestic flea,” _Pulex irritans_, is too well known to need much description. They deposit their eggs, which are tiny ribbed crystalline spheres (very beautiful objects under the microscope) in the dry dust in cracks and crannies in the floor, or in the corners of badly-swept rooms. From these eggs hatch out slender, legless, transparent grubs with several short bristles on the anal extremity; these grubs feed upon the dust and, when full grown, spin a silken tube in which they pupate buried in the dust.

_P. serraticeps_ is known as the dog and cat flea, though it is not uncommon at times in the house where animals are running about; but though it sometimes comes on man, it is an accidental infestation, and it gets away to its natural host as soon as it can escape. It can be easily distinguished from the common house flea by its more elongate form, and by the black comb-like spines fringing the back of the head and the first thoracic segment, which are absent in the former.

The Rat and Mouse Flea, _P. fasciatus_, is a paler coloured, more slender flea, also with a very extended range over the world. It is notorious as the species that, when living upon plague-infested rats, can transmit bubonic plague to man.

Denny (Annals and Mag. Nat. Hist. XII. 1843) has described another species, which he placed in this Genus, obtained from Tasmania and found upon the _Echidna_, and which he has called _Pulex echidnae_. About a dozen indigenous species have been recorded from Australia.

The Genus _Echidnophaga_ was created by Olliff (Pro. Linn. Soc. N.S.W. 1886) to contain a species he described under the name of _Echidnophaga ambulans_; it is remarkable for its very long proboscis, and short legs which render it unable to jump. Large numbers of this flea were found upon a Porcupine Ant Eater (_Echidna hystrix_) in the Australian Museum. Messrs. Jordan and Rothschild in the Revision previously noticed place 8 species in Olliff’s Genus, adding two more to the Australian fauna, _E. macronychia_ from West Australia found upon a small marsupial (_Bettongia lesueuri_), and _E. liopus_ also from West Australia on _Echidna aculeata_, at the same time recording the last-named species upon rats at Agra, India. They give a number of additional hosts of _E. ambulans_, namely: the opossum, several other marsupials, and the brown snake; and they extend its range from Sydney to West Australia.

The Chicken Flea, _E. gallinaceus_, which they place in this Genus (originally described by Westwood under the generic name _Sarcopsylla_) though it has not been recorded from Australia has a range from America, Africa, and Russia to Fiji; it infests a great number of both wild and domestic animals and birds.

Skuse (Annals of the Australian Museum 1893) described a very curious flea, found in the pouch of a native cat (_Dasyurus_) which he called _Stephanocircus dasyuri_. I have since had the typical legless larvae, found also in the marsupial pouch of the same animal, and it is also common upon the bandicoot in Queensland. This flea has an elongate body, with the front of the head flattened and fringed with fine spines; it has no eyes.

Skuse is said to have described two species belonging to different genera as the sexes of his flea; and Rainbow in the same journal (Records Aust. Mus. 1905) proposes the name of _Ceratophyllus rothschildi_ for the second. Rothschild has described two other species in this genus, _C. hilli_ from N.S. Wales on the native cat, and a second, _C. woodwardi_, from W. Australia.

[Illustration: =Fig. 153.=--_Stephanocircus dasyuri_ (Skuse).

Flea of the “Native-cat” and “Bandicoot.”

(Original photo. G. Turner.)]

Rothschild also describes two other species which he places in Skuse’s Genus _Stephanocircus_, namely _S. thomasi_ (Nov. Zool. X. 1903) from Barrow Island N.W. Australia, and _S. simsoni_ (Entomologists’ Month. Magazine XVI. 1905), which comes from Tasmania, taken upon a native cat, _Dasyurus maculatus_. In the Entomologists’ Monthly Magazine 1906 Rothschild forms a new Genus _Pygiopsylla_ for a large Tasmanian flea taken on a native rat which he calls _Pygiopsylla colossus_. He makes _Ceratophyllus hilli_ the type of this new genus, in which he also places three other Australian species originally described in the latter genus, namely: _C. woodwardi_, _rothschildi_, and _echidnae_, in the new one.

Order VIII.--HEMIPTERA.

Bugs, Frog-hoppers, Scale Insects, &c.

The structure of the mouth is the distinctive character of the insects of this great Order. Instead of the biting jaws (or sucking mouth) of many other insects previously described it is produced into a slender pointed tube of complicated structure, which usually lies along the under-surface of the head and thorax. This beak, called the rostrum, consists of a jointed sheath (labium) enclosing hair-like setae (mandibles and maxillae). When the insect feeds the sharp tip is pressed into its food, and the sap or juice sucked up, not by the proboscis-like sheath, but by the delicate enclosed setae. Kirkaldy doubts if the sheath “ever even penetrates the tissues, either vegetable or animal, unless these be already lacerated by the setae”; and it is often used only as a fulcrum to steady their operations.

In the outward appearance (often a deceptive character in classification) the members of this group are very dissimilar; probably no two insects could be more unlike than the typical plant bug and the ordinary scale insect.

They all undergo an incomplete metamorphosis, often changing their colours and even shape in the various moults before they are fully developed. The eggs of those living upon plants are generally deposited in clusters, and these are often very beautiful crystal spheres with stellate caps upon the summits. In other groups the eggs are buried in the tissue of the food plant or covered with woolly or sticky secretions.

They take the name Hemiptera from the structure of the fore wing, one half of which is, in the typical bugs, horny and the rest semitransparent.

The families of the plant and water bugs are much more closely related to each other than to the frog-hoppers, cicades and scale insects; and the whole Order has been separated into groups or sub-orders, viz., HETEROPTERA; HOMOPTERA; ANOPLURA; MALLOPHAGA.

Sub-order I. HETEROPTERA.

Bugs.

This sub-division contains all the plant, carnivorous, and water bugs, which vary in size and shape from the tiny little leaf-infesting forms to the great “fish-killer,” _Belostoma indicum_, found in our water-holes.

They are usually furnished with two pairs of wings. The basal portion of the front pair is horny and opaque, and the apical half more or less transparent; this pair covers the larger hind pair, which, well adapted for flight, are folded up beneath when at rest. The members of some groups however are apterous.

Many are furnished with glands on the body secreting an offensive, buggy-smelling fluid, which they discharge when handled or disturbed.

Some species are serious pests to plant life, and swarm in countless thousands over vegetation, sucking up the sap and causing it to wither and die in consequence, as in the case of the Chinch Bug of North America upon wheat, and the Rutherglen Bug in Australia among field crops. Others are predaceous and very useful, destroying great numbers of leaf-eating grubs and caterpillars.

These insects are well represented in Australia, and many of the larger and more showy ones were collected and described at a very early date, and their descriptions are scattered through the pages of many scientific journals. Numbers of our species have been described by Westwood (Hope Catal. 1837); Dallas (List Hemip. 1851); Walker (Catal. Heter. Brit. Museum 1867); Distant (Trans. Ent. Soc. London, 1886, etc.); Kirkaldy (The Entomologist); and others in English journals; while among the Continental writers Messrs. Stal, Bergroth, Montandon, Horvath, and Reuter have been the chief workers.

In 1893 Messrs. Lethierry and Severin commenced a “Catalogue of the Described Heteroptera of the World”; three parts were published, but, probably owing to the death of Lethierry, it was never completed,