Part V

. (Jan. 1837.) p. 9.

_M. Fæm. fuscescenti-niger, marginibus plumarum inter scapulas fulvis; primariis secundariisque albo ad apicem notatis; gulá, pectore, corporeque subtùs albis; lateribus fusco sparsis; rostro livido, lineis nigris ornato; cerâ tarsisque flavis._

Long. tot. 20 unc. ½ rostri, 1⅝; alæ, 15¾; caudæ, 9; tarsi, 3.

_Description of female specimen, believed to be applicable to both sexes._

COLOUR.—Head, back, upper wing coverts pitch black, passing into liver brown; feathers on back of neck and shoulders terminating in a yellowish brown tip, of which tint the external portion of the primaries, and nearly the whole of the tertiaries partake. Tail liver brown, with a terminal white band nearly one inch broad; base of the tectrices white, irregularly marked with brown: upper tail coverts white. All the feathers of the wing tipped with white, their bases irregularly barred with transverse marks of brown and white. _Under surface._—Chin, throat, breast, belly, thighs, under tail-coverts, under lining of wings, and edge of shoulders perfectly white. On the flanks, however, there are some brown feathers irregularly interspersed; and on the lower part of the breast, most of the feathers show a most obscure margin of pale brown. Bill horn colour. Cere and tarsi yellow.

[Illustration:

_Birds. Pl. 1._

_Milvago albogularis_ ]

FORM.—Cere and nostril as in the _M. Leucurus_, but the bill not quite so strong. Feathers on the sides and back of head narrow and rather stiff; those on the shoulders obtusely pointed,—which character of plumage is very general in this sub-family. Wing: fourth primary very little longer than the third or the fifth, which are equal to each other. First primary three inches shorter than the fourth or longest, and more nearly equal to the sixth than to the seventh. Extremity of wing reaching to within about an inch and a half of the tail. Tarsi reticulated, with four large scales at the base: upper part covered with plumose feathers for about three quarters of an inch below the knee; but these feathers hang down and cover nearly half of the leg. Middle toe with fifteen scales, outer ones with about nine. Claws of nearly the same degree of strength, curvature and breadth as in _Polyborus Brasiliensis_, or in _M. leucurus_, but sharper than those of the latter.

Inch. Total length 20½ Tail 9 Wings when folded 15¾ From tip of beak to anterior edge of eye ⁹⁄₁₀ Tarsus from soles of feet to knee joint 3½ Hind claw measured in straight line from tip to root ⁸⁄₁₀ Claw of middle toe, a twentieth less than that of the hind one.

Habitat, Santa Cruz, 50° S. Patagonia. (_April._)

Mr. Gould, at the time of describing this species, entertained some doubts whether it might not eventually prove to be the _Phalcobænus montanus_ of D’Orbigny, in a state of change. I have carefully compared it with the description of the _P. montanus_, and certainly, with the exception of the one great difference of _M. albogularis_ having a white breast, whilst that part in the _P. montanus_ is black, the points of resemblance are numerous and exceedingly close. The _M. albogularis_, appears to be rather larger, and the proportional length of the wing feathers are slightly different; the cere and tarsi are not of so bright a colour; the middle toe has fifteen scales on it instead of having sixteen or seventeen. The black shades of the upper surface are pitchy, instead of having an obscure metallic gloss, and the feathers of the shoulders are terminated with brown, so as to form a collar, which is not represented in the figure of _P. montanus_, given by M. D’Orbigny. Although the main difference between the two birds, is the colour of their breasts, yet it must be observed, that in the _M. albogularis_ there is some indication of an incipient change from white to brown in the plumage of that part. But as M. D’Orbigny, who was acquainted with the young birds of the _P. montanus_, (of which he has given a figure), does not mention so remarkable a modification in its plumage, as must take place on the supposition of _M. albogularis_ being an immature bird of that species; and as the geographical range of the two is so very different, I am induced to consider them distinct. Moreover, on the plains of Santa Cruz, I saw several birds, and they appeared to me similar in their colouring. The _M. albogularis_ is remarkable from the confined locality which it appears to frequent. A few pair were seen during the ascent of the river Santa Cruz, (Lat. 50° S.) to the Cordillera; but not one individual was observed in any other part of Patagonia. They appeared to me to resemble, in their gait and manner of flight, the _P. Brasiliensis_; but they were rather wilder. They lived in pairs, and generally were near the river. One day I observed a couple standing with the Carranchas and _M. pezoporus_, at a short distance from the carcass of a guanaco, on which the condors had commenced an attack. These peculiarities of habit are described by M. D’Orbigny in almost the same words, as occurring with the _P. montanus_; both birds frequent desert countries; the _P. montanus_, however, haunts the great mountains of Bolivia, and this species, the open plains of Patagonia.

In the valleys north of 30° in Chile, I saw several pair, either of this species, or of the _P. montanus_ of D’Orbigny, (if, as is probable, they are different) or of some third kind. From the circumstance of its not extending (as I believe) so far south even as the valley of Coquimbo, it is extremely improbable that it should be the _M. albogularis_,—an inhabitant of a plain country twenty degrees further south. On the other hand, the _P. montanus_ lives at a great elevation on the mountains of Upper Peru; and therefore it is probable that it might be found in a higher latitude, but at a less elevation. M. D’Orbigny says, “Elle aime les terrains secs et dépourvus de grands végétaux, qui lui seraient inutiles; car il nous est prouvé qu’elle ne se perche pas sur les branches.” In another part he adds, “Elle descend cependant quelquefois jusque près de la mer, sur la côte du Pérou, mais ce n’est que pour peu de temps, et peut-être afin d’y chercher momentanément une nourriture qui lui manque dans son séjour habituel; peut-être aussi la nature du sol l’y attire-t-elle; car elle y trouve les terrains arides qui lui sont propres.”[9] This is so entirely the character of the northern parts of Chile, that, it appears to me extremely probable, that the _P. montanus_, which inhabits the great mountains of Bolivia, descends, in Northern Chile, to near the shores of the Pacific; but that further south, and on the opposite side of the Cordillera, it is replaced by an allied species,—the _M. albogularis_ of Santa Cruz.

5. MILVAGO MEGALOPTERUS.

Aquila megaloptera, _Meyen_, Nov. Act. Acad. Cæs. Suppl. 1834, p. 64. Pl. VIII.

When ascending the Despoblado, a branch of the valley of Copiapó in Northern Chile, I saw several brown coloured hawks, which at the time appeared new to me, but of which I did not procure a specimen. These I have no doubt were the _A. megaloptera_ of Meyen. In the British Museum there is a specimen, brought from Chile by Mr. Crawley. Mr. G. R. Gray suspects that this bird may eventually prove to be the young of the _Phalcobænus montanus_ of D’Orbigny, and as I saw that bird (or another species having a close general resemblance with it) in the valleys of Northern Chile, although not in the immediate vicinity, this supposition is by no means improbable. Meyen’s figure at first sight appears very different from that of the young of the _P. montanus_, given by M. D’Orbigny, for in the latter the feathers over nearly the whole body are more distinctly bordered with a pale rufous shade, the thighs barred with the same, and the general tint is of a much redder brown. But with the exception of these differences, which are only in degree, I can find in M. D’Orbigny’s description no other distinguishing character, whilst on the other hand, there are numerous points of close resemblance between the two birds in the shadings, and even trifling marks of their plumage. Meyen, moreover, in describing the habits of his species, says, it frequents a region just below the limit of perpetual snow, and that it sometimes soars at a great height like a condor. Those which I saw had the general manners of a _Polyborus_ or _Milvago_, and were flying from rock to rock amongst the mountains at a considerable elevation, but far below the snow-line. In these several respects, there is a close agreement with the habits of the _P. montanus_, as described by M. D’Orbigny. I will only add that the specimen in the British Museum appeared, independently of differences of plumage, distinct from the _M. albogularis_ of Patagonia, from the thinness and greater prolongation of its beak, and the slenderness of its tarsi.

SUB-FAM.—BUTEONINÆ. CRAXIREX. _Gould._

_Rostrum Buteonis sed longius; mandibulæ superioris margo rectus; versus apicem subitò incurvus. Alæ elongatæ. Cera lata. Nares ferè rotundæ, apertæ. Tarsi mediocres, anticè squamis tecti. Digiti magni, fortes; ungues obtusæ._

Mr. Gould was partly led to institute this genus from the facts communicated to him by me regarding the habits of the following species, which is found in the Galapagos Archipelago, and there supplies the place of the Polybori and Milvagines of the neighbouring continent of America. If a principle of classification founded on habits alone, were admissible, this bird, as will presently be shown, undoubtedly would be ranked with more propriety in the sub-family of Polyborinæ, than amongst the Buzzards. To the latter it is closely related in the form of its nostrils; in the kind of plumage which covers the head, breast, and shoulders; in the reticulation of the scales on its feet and tarsi, and less closely in the form of its beak. To the Polyborinæ it manifests an affinity in the great strength and length of its toes and claws, and in the bluntness of the latter; in the nakedness of the cere, in the perfectly uncovered nostrils, in the prolongation and bulk of the bill, in the straightness of the line of commissure, and in the narrow shape of the head. In these several respects, taken conjointly with its habits, this bird supplies a most interesting link in the chain of affinities, by which the true buzzards pass into the great American sub-family of carrion-feeding hawks. I am, indeed, unable to decide, whether I have judged rightly in placing this genus, as first of the Buteoninæ, instead of last of the Polyborinæ.

[Illustration:

_Birds. Pl. 2._

_Craxirex Galapagoensis_ ]

CRAXIREX GALAPAGOENSIS. _Gould._

PLATE II.

Polyborus Galapagoensis. Proceedings of the Zoological Society for January, 1837, p. 9.

_C. Mas. adult, Intensè fuscus; primariis nigris; secundariarum pogoniis internis transversim albo et fusco striatis; caudâ cinerascenti-fuscâ, transversim lineis angustis et numerosis intensè fuscis notatâ; rostro obscure corneo; pedibus olivaceo-flavis._

Long. tot. 20½ unc.; _rostri_, 1½; _alæ_, 15; _caudæ_, 8½; _tarsi_, 3¼.

_Fæm. adult, fæminæ juniori ferè similis, pectore tamen fusco._

_Fæm. juv. Capite corporeque intensè stramineis, fusco-variegatis; illo in pectore et abdomine prævalente; primariis fusco-nigris; rectricum pogoniis externè cinerascenti-fuscis, internè pallide rosaceis; utrisque lineis angustis et frequentibus fuscis transversim striatis, apicibus sordide albis; rostro nigrescenti-fusco; pedibus olivaceo-flavis._

Long. tot. 24 unc.; _rostri_, 1¾; _alæ_, 17¼; _caudæ_, 10½; _tarsi_, 3½.

_Description of adult male._

COLOUR.—Entire dorsal aspect umber brown: base of feathers on hind part of neck, white; base of those on back, irregularly banded with pale fulvous, and the scapulars with a distinct band of it. The inferior feathers of upper tail coverts banded in like manner to their extremities. Tail dusky clove brown, obscurely marked with darkened transverse narrow bands. Primaries perfectly black towards their extremities, but with the outer edge of their base, gray: inner web banded and freckled with gray, brown, and white, which in the secondaries takes the form of regular bars. _Under surface_, entirely umber brown, but rather paler than the upper. Lining of wings gray, with irregular transverse brown bars: under-side of tail the same, but paler. Thighs of a rather yellower brown. Bill and cere horn colour, mottled with pale gray: tarsi yellow.

FORM.—Beak, with apex much arched, both longer and more pointed than it is in the group of the Polyborinæ. Cere naked, with few bristles; nostrils large, quite uncovered, irregularly triangular, with the angles much rounded, and situated rather above a central line between the culmen and commissure. Fourth primary longest, but third and fifth nearly equal to it; first, four inches and a half shorter than fourth, and equal to the eighth; second shorter than fifth. Extremities of wing reaching within half an inch of end of tail. Tarsi strong, feathered for nearly a third of their length beneath the joint. Scales in narrow, undivided (with the exception in some instances of one) bands, covering the front of tarsus. Toes very strong and rather long, like those of the species of _Milvago_, and much more so than in the genus _Buteo_. Hind-toe equal in length to the inner one; but not placed quite so high on the Tarsus as in _Polyborus_. Basal joints of middle toe covered with small scales, with five large ones towards the extremity. Claws very strong, thick and long, and rather more arched, and broader than in _Polyborus Brasiliensis_; their extremities obtuse, but not in so great a degree as in some species of _Milvago_.

Inches. Total length from tip of bill to end of tail following curvature of body 20½ Tail 8½ Wing, from elbow-joint to extremity of longest primary 15 Bill, from tip to anterior edge of eye measured in a straight line ⁷⁄₁₀ Tarsus, from soles of feet to centre of joint 3½ Hind claw from tip to root, measured in straight line 1⅒ Claw of middle toe ⁹⁵⁄₁₀₀

_Old female._

COLOUR.—Nearly as in young female, but with the breast dark brown.

_Young female._

COLOUR.—Head, back of neck, back, wing coverts and tertiaries barred and mottled, both with pale umber brown (of the same tint as in the male bird) and with pale fulvous orange. On head and back of neck, each feather is of the latter colour, with a mere patch of the brown on its tip; but in the longer feathers, as in the scapulars, upper tail coverts, inner web and part of outer of the tertiaries, each is distinctly barred with the dark brown. Tail as in the old male. Primaries black as in male, with the inner webs nearly white, and marked with short transverse bars. Under surface and thighs of the same fulvous orange, but some of the feathers, especially those on the breast, are marked with small spots of umber brown on their tips. Some of the longer feathers on the flanks, on the under tail coverts, and on the linings of the wing, have irregular bars of the same.

FORM and SIZE.—Larger and more robust than the male. Total length 24 inches. Tail ten and a half inches long, and therefore longer in proportion to the wings than in the other sex. Wings from joint to end of primaries, 17¼.

Habitat, Galapagos Archipelago, (_October_).

This bird is, I believe, confined to the Galapagos Archipelago, where on all the islands, it is excessively numerous. It inhabits, indifferently, either the dry sterile region near the coast, which, perhaps, is its most general resort, or the damp and wooded summits of the volcanic hills. This bird, in most of its habits and disposition, resembles the _Milvago leucurus_, or the _Falco Novæ Zelandiæ_ of older authors. It is extremely tame, and frequents the neighbourhood of any building inhabited by man. When a tortoise is killed even in the midst of the woods, these birds immediately congregate in great numbers, and remain either seated on the ground, or on the branches of the stunted trees, patiently waiting to devour the intestines, and to pick the carapace clean, after the meat has been cut away. These birds will eat all kinds of offal thrown from the houses, and dead fish and marine productions cast up by the sea. They are said to kill young doves, and even chickens; and are very destructive to the little tortoises, as soon as they break through the shell. In these respects this bird shows its alliance with the buzzards. Its flight is neither elegant nor swift. On the ground it is able, like the _M. leucurus_ and _Phalcobænus montanus_ of D’Orbigny, to run very quickly. This habit which, as before observed, is so anomalous in the Falcons, manifests in a very striking manner the relation of this new genus with the _Polyborinæ_. It is, also, a noisy bird, and utters many different cries, one of which was so very like the shrill gentle scream of the _M. chimango_, that the officers of the “Beagle” generally called it either by this name, or from its larger size by that of _Carrancha_,—both names, however, plainly indicating its close and evident relationship with the birds of that family. The craw is feathered; and does not, I believe, protrude like that of the _P. Brasiliensis_ or _M. leucurus_. It builds in trees, and the female was just beginning to lay in October. The bird of which the full figure has been given, is a young female, but of, at least, one year old. The old male bird is of a uniform dusky plumage, and is seen behind. The adult female resembles the young of the same sex, but the breast is dark brown like that of the male. In precisely the same manner as was remarked in the case of the _M. leucurus_, these old females are present in singularly few proportional numbers. One day at James’ Island, out of thirty birds, which I counted standing within a hundred yards of the tents, under which we were bivouacked, there was not a single one with the dark brown breast. From this circumstance I am led to conclude that the females of this species (as with the _M. leucurus_) acquire their full plumage late in life.

1. BUTEO ERYTHRONOTUS.

Haliaëtus erythronotus, _King_, in Zoological Journal, vol. iii. p. 424. Buteo tricolor, _D’Orbigny_.

I obtained specimens of this bird from Chiloe and the Falkland Islands, and Captain King who first described it, procured his specimens from Port Famine, Lat. 53° 38′ in Tierra del Fuego. M. D’Orbigny states that it has a wide range over the provinces of La Plata, central Chile, and even Bolivia; but in this latter country, it occurs only on the mountains, at an elevation of about 12,000 feet above the sea. The same author states, that it usually frequents open and dry countries; but as we now see that it is found in the dense and humid forests of Chiloe and Tierra del Fuego, this remark is not applicable. At the Falkland Islands, it preys chiefly on the rabbits, which have run wild and abound over certain parts of the island. This bird was considered by Captain King as a _Haliaëtus_; but Mr. Gould thinks it is more properly placed with the Buzzards. Captain King gave it the appropriate specific name of _erythronotus_, and, therefore, as Mr. Gould observes, the more recent one of _tricolor_, given by M. D’Orbigny, must be passed over.

2. BUTEO VARIUS. _Gould._

Buteo varius, _Gould_, Proceedings of the Zoological Society,