CHAPTER XIX

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MUSIC AND DANCING IN NATURE.

In reading books of Natural History we meet with numerous instances of birds possessing the habit of assembling together, in many cases always at the same spot, to indulge in antics and dancing performances, with or without the accompaniment of music, vocal or instrumental; and by instrumental music is here meant all sounds other than vocal made habitually and during the more or less orderly performances; as, for instance, drumming and tapping noises; smiting of wings; and humming, whip-cracking, fan-shutting, grinding, scraping, and horn-blowing sounds, produced as a rule by the quills.

There are human dances, in which only one person performs at a time, the rest of the company looking on; and some birds, in widely separated genera, have dances of this kind. A striking example is the Rupicola, or cock of-the-rock, of tropical South America. A mossy level spot of earth surrounded by bushes is selected for a dancing-place, and kept well cleared of sticks and stones; round this area the birds assemble, when a cock-bird, with vivid orange-scarlet crest and plumage, steps into it, and, with spreading wings and tail, begins a series of movements as if dancing a minuet; finally, carried away with excitement, he leaps and gyrates in the most astonishing manner, until, becoming exhausted, he retires, and another bird takes his place.

In other species all the birds in a company unite in the set performances, and seem to obey an impulse which affects them simultaneously and in the same degree; but sometimes one bird prompts the others and takes a principal part. One of the most curious instances I have come across in reading is contained in Mr. Bigg-Wither's _Pioneering in South Brazil._ He relates that one morning in the dense forest his attention was roused by the unwonted sound of a bird singing--songsters being rare in that district. His men, immediately they caught the sound, invited him to follow them, hinting that he would probably witness a very curious sight. Cautiously making their way through the dense undergrowth, they finally came in sight of a small stony spot of ground, at the end of a tiny glade; and on this spot, some on the stone and some on the shrubs, were assembled a number of little birds, about the size of tom-tits, with lovely blue plumage and red top-knots. One was perched quite still on a twig, singing merrily, while the others were keeping time with wings and feet in a kind of dance, and all twittering an accompaniment. He watched them for some time, and was satisfied that they were having a ball and concert, and thoroughly enjoying themselves; they then became alarmed, and the performance abruptly terminated, the birds all going off in different directions. The natives told him that these little creatures were known as the "dancing birds."

This species was probably solitary, except when assembling for the purpose of display; but in a majority of cases, especially in the Passerine order, the solitary species performs its antics alone, or with no witness but its mate. Azara, describing a small finch, which he aptly named _Oscilador,_ says that early and late in the day it mounts up vertically to a moderate height; then, flies off to a distance of twenty yards, describing a perfect curve in its passage; turning, it flies back over the imaginary line it has traced, and so on repeatedly, appearing like a pendulum swung in space by an invisible thread.

Those who seek to know the cause and origin of this kind of display and of song in animals are referred to Darwin's _Descent of Man_ for an explanation. The greater part of that work is occupied with a laborious argument intended to prove that the love-feeling inspires the animals engaged in these exhibitions, and that sexual selection, or the voluntary selection of mates by the females, is the final cause of all set musical and dancing performances, as well as of bright and harmonious colouring, and of ornaments.

The theory, with regard to birds is, that in the love-season, when the males are excited and engage in courtship, the females do not fall to the strongest and most active, nor to those that are first in the field; but that in a large number of species they are endowed with a faculty corresponding to the aesthetic feeling or taste in man, and deliberately select males for their superiority in some aesthetic quality, such as graceful or fantastic motions, melody of voice, brilliancy of colour, or perfection of ornaments. Doubtless all birds were originally plain-coloured, without ornaments and without melody, and it is assumed that so it would always have been in many cases but for the action of this principle, which, like natural selection, has gone on accumulating countless small variations, tending to give a greater lustre to the species in each case, and resulting in all that we most admire in the animal world--the Rupicola's flame-coloured mantle, the peacock's crest and starry train, the joyous melody of the lark, and the pretty or fantastic dancing performances of birds.

My experience is that mammals and birds, with few exceptions--probably there are really no exceptions--possess the habit of indulging frequently in more or less regular or set performances, with or without sound, or composed of sound exclusively; and that these performances, which in many animals are only discordant cries and choruses, and uncouth, irregular motions, in the more aerial, graceful, and melodious kinds take immeasurably higher, more complex, and more beautiful forms. Among the mammalians the instinct appears almost universal; but their displays are, as a rule, less admirable than those seen in birds. There are some kinds, it is true, like the squirrels and monkeys, of arboreal habits, almost birdlike in their restless energy, and in the swiftness and certitude of their motions, in which the slightest impulse can be instantly expressed in graceful or fantastic action; others, like the Chinchillidae family, have greatly developed vocal organs, and resemble birds in loquacity; but mammals generally, compared with birds, are slow and heavy, and not so readily moved to exhibitions of the kind I am discussing.

The terrestrial dances, often very elaborate, of heavy birds, like those of the gallinaceous kind, are represented in the more volatile species by performances in the air, and these are very much more beautiful; while a very large number of birds--hawks, vultures, swifts, swallows, nightjars, storks, ibises, spoonbills, and gulls--circle about in the air, singly or in flocks. Sometimes, in serene weather, they rise to a vast altitude, and float about in one spot for an hour or longer at a stretch, showing a faint bird-cloud in the blue, that does not change its form, nor grow lighter and denser like a flock of starlings; but in the seeming confusion there is perfect order, and amidst many hundreds each swift- or slow-gliding figure keeps its proper distance with such exactitude that no two ever touch, even with the extremity of the long-wings, flapping or motionless:--such a multitude, and such miraculous precision in the endless curving motions of all the members of it, that the spectator can lie for an hour on his back without weariness watching this mystic cloud-dance in the empyrean.

The black-faced ibis of Patagonia, a bird nearly as large as a turkey, indulges in a curious mad performance, usually in the evening when feeding-time is over. The birds of a flock, while winging their way to the roosting-place, all at once seem possessed with frenzy, simultaneously dashing downwards with amazing violence, doubling about in the most eccentric manner; and when close to the surface rising again to repeat the action, all the while making the air palpitate for miles around with their hard, metallic cries. Other ibises, also birds of other genera, have similar aerial performances.

The displays of most ducks known to me take the form of mock fights on the water; one exception is the handsome and loquacious whistling widgeon of La Plata, which has a pretty aerial performance. A dozen or twenty birds rise up until they appear like small specks in the sky, and sometimes disappear from sight altogether; and at that great altitude they continue hovering in one spot, often for an hour or longer, alternately closing and separating; the fine, bright, whistling notes and flourishes of the male curiously harmonizing with the grave, measured notes of the female; and every time they close they slap each other on the wings so smartly that the sound can be distinctly heard, like applauding hand-claps, even after the birds have ceased to be visible.

The rails, active, sprightly birds with powerful and varied voices, are great performers; but owing to the nature of the ground they inhabit and to their shy, suspicious character, it is not easy to observe their antics. The finest of the Platan rails is the ypecaha, a beautiful,

## active bird about the size of the fowl. A number of ypecahas have their

assembling place on a small area of smooth, level ground, just above the water, and hemmed in by dense rush beds. First, one bird among the rushes emits a powerful cry, thrice repeated; and this is a note of invitation, quickly responded to by other birds from all sides as they hurriedly repair to the usual place. In a few moments they appear, to the number of a dozen or twenty, bursting from the rushes and running into the open space, and instantly beginning the performance. This is a tremendous screaming concert. The screams they utter have a certain resemblance to the human voice, exerted to its utmost pitch and expressive of extreme terror, frenzy, and despair. A long, piercing shriek, astonishing for its vehemence and power, is succeeded by a lower note, as if in the first the creature had well nigh exhausted itself: this double scream is repeated several times, and followed by other sounds, resembling, as they rise and fall, half smothered cries of pains and moans of anguish. Suddenly the unearthly shrieks are renewed in all their power. While screaming the birds rush from side to side, as if possessed with madness, the wings spread and vibrating, the long-beak wide open and raised vertically. This exhibition lasts three or four minntes, after which the assembly peacefully breaks up.

The singular wattled, wing-spurred, and long-, toed jacana has a remarkable performance, which seems specially designed to bring out the concealed beauty of the silky, greenish-golden wing-quills-The birds go singly or in pairs, and a dozen or fifteen individuals may be found in a marshy place feeding within sight of each other. Occasionally, in response to a note of invitation, they all in a moment leave off feeding and fly to one spot, and, forming a close cluster, and emitting short, excited, rapidly repeated notes, display their wings, like beautiful flags grouped loosely together: some hold the wings up vertically and motionless; others, half open and vibrating rapidly, while still others wave them up and down with a slow, measured motion.

In the ypecaha and jacana displays both sexes take part. A stranger performance is that of the spur-winged lapwing of the same region--a species resembling the lapwing of Europe, but a third larger, brighter coloured, and armed with spurs. The lapwing display, called by the natives its "dance," or "serious dance"--by which they mean square dance--requires three birds for its performance, and is, so far as I know, unique in this respect. The birds are so fond of it that they indulge in it all the year round, and at frequent intervals during the day, also on moonlight nights. If a person watches any two birds for some time--for they live in pairs--he will see another lapwing, one of a neighbouring couple, rise up and fly to them, leaving his own mate to guard their chosen ground; and instead of resenting this visit as an unwarranted intrusion on their domain, as they would certainly resent the approach of almost any other bird, they welcome it with notes and signs of pleasure. Advancing to the visitor, they place themselves behind it; then all three, keeping step, begin a rapid march, uttering resonant drumming notes in time with their movements; the notes of the pair behind being emitted in a stream, like a drum-roll, while the leader utters loud single notes at regular intervals. The march ceases; the leader elevates his wings and stands erect and motionless, still uttering loud notes; while the other two, with puffed-out plumage and standing exactly abreast stoop forward and downward until the tips of their beaks touch the ground, and, sinking their rhythmical voices to a murmur, remain for some time in this posture. The performance is then over and the visitor goes back to his own ground and mate, to receive a visitor himself later on.

In the Passerine order, not the least remarkable displays are witnessed in birds that are not accounted songsters, as they do not possess the highly developed vocal organ confined to the suborder Oscines. The tyrant-birds, which represent in South America the fly-catchers of the Old World, all have displays of some kind; in a vast majority of cases these are simply joyous, excited duets between male and female, composed of impetuous and more or less confused notes and screams, accompanied with beating of wings and other gestures. In some species choruses take the place of duets, while in others entirely different forms of display have been developed. In one group--Cnipolegus--the male indulges in solitary antics, while the silent, modest-coloured female keeps in hiding. Thus, the male of Cnipolegus Hudsoni, an intensely black-plumaged species with a concealed white wing-band, takes his stand on a dead twig on the summit of a bush. At intervals he leaves his perch, displaying the intense white on the quills, and producing, as the wings are thrown open and shut alternately, the effect of successive flashes of light. Then suddenly the bird begins revolving in the air about its perch, like a moth wheeling round and close to the flame of a candle, emitting a series of sharp clicks and making a loud humming with the wings. While performing this aerial waltz the black and white on the quills mix, the wings appearing like a grey mist encircling the body. The fantastic dance over, the bird drops suddenly on to its perch again; and, until moved to another display, remains as stiff and motionless as a bird carved out of jet.

The performance of the scissors-tail, another tyrant-bird, is also remarkable. This species is grey and white, with black head and tail and a crocus-yellow crest. On the wing it looks like a large swallow, but with the two outer tail-feathers a foot long. The scissors-tails always live in pairs, but at sunset several pairs assemble, the birds calling excitedly to each other; they then mount upwards, like rockets, to a great height in the anand, after wheeling about for a few moments, pro-cipitate themselves downwards with amazing violence in a wild zigzag, opening and shutting the long tail-feathers like a pair of shears, and producing loud whirring sounds, as of clocks being wound rapidly up, with a slight pause after each turn of the key. This aerial dance over, they alight in separate couples on the tree tops, each couple joining in a kind of duet of rapidly repeated, castanet-like sounds.

The displays of the wood-hewers, or Dendrocolap-tidae, another extensive family, resemble those of the tyrant-birds in being chiefly duets, male and female singing excitedly in piercing or resonant voices, and with much action. The habit varies somewhat in the cachalote, a Patagonian species of the genus Homorus, about the size of the missel-thrush. Old and young birds live in a family together, and at intervals, on any fine day, they engage in a grand screaming contest, which may be heard distinctly at a distance of a mile and a half. One bird mounts on to a bush and calls, and instantly all the others hurry to the spot, and burst out into a chorus of piercing cries that sound like peals and shrieks of insane laughter. After the chorus, they all pursue each other wildly about among the bushes for some minutes.

In some groups the usual duet-like performances have developed into a kind of harmonious singing, which is very curious and pleasant to hear. This is pre-eminently the case with the oven-birds, as D'Orbigney first remarked. Thus, in the red oven-bird, the first bird, on the appearance of its mate flying to join it, begins to emit loud, measured notes, and sometimes a continuous trill, somewhat metallic in sound; but immediately on the other bird striking in this introductory passage is changed to triplets, strongly accented on the first note, in a _tempo vivace;_ while the second bird utters loud single notes in the same time. While thus singing they stand facing each other, necks outstretched and tails expanded, the wings of the first bird vibrating rapidly to the rapid utterance, while those of the second bird beat measured time. The finale consists of three or four notes, uttered by the second bird alone, strong and clear, in an ascending scale, the last very piercing.

In the melodists proper the displays, in a majority of cases, are exclusively vocal, the singer sitting still on his perch. In the Troupials, a family of starling-like birds numbering about one hundred and forty species, there are many that accompany singing with pretty or grotesque antics. The male screaming cow-bird of La Plata, when perched, emits a hollow-sounding internal note that swells at the end into a sharp metallic ring, almost bell-like: this is uttered with wings and tail spread and depressed, the whole plumage being puffed out as in a strutting turkey-cock, while the bird hops briskly up and down on its perch as if dancing. The bell-like note of the male is followed by an impetuous scream from the female, and the dance ends. Another species, the common Argentine cow-bird of La Plata, when courting puffs out his glossy rich violet plumage, and, with wings vibrating, emits a succession of deep internal notes, followed by a set song in clear, ringing tones; and then, suddenly taking wing, he flies straight away, close to the surface, fluttering like a moth, and at a distance of twenty to thirty yards turns and flies in a wide circle round the female, singing loudly all the time, hedging her in with melody as it were.

Many songsters in widely different families possess the habit of soaring and falling alternately while singing, and in some cases all the aerial postures and movements, the swift or slow descent, vertical, often, with oscillations, or in a spiral, and sometimes with a succession of smooth oblique lapses, seem to have an admirable correspondence with the changing and falling voice--melody and motion being united in a more intimate and beautiful way than in the most perfect and poetic forms of human dancing.

One of the soaring singers is a small yellow field-finch of La Plata--Sycalis luteola; and this species, like some others, changes the form of its display with the seasons. It lives in immense flocks, and during the cold season it has, like most finches, only aerial pastimes, the birds wheeling about in a cloud, pursuing each other with lively chirpings. In August, when the trees begin to blossom, the flock betakes itself to a plantation, and, sitting on the branches, the birds sing in a concert of innumerable voices, producing a great volume of sound, as of a high wind when heard at a distance. Heard near, it is a great mass of melody; not a confused tangle of musical sounds as when a host of Troupials sing in concert, but the notes, although numberless, seem to flow smoothly and separately, producing an effect on the ear similar to that which rain does on the sight, when the sun shines on and lightens up the myriads of falling drops all falling one way. In this manner the birds sing for hours, without intermission, every day. Then the passion of love infects them; the pleasant choir breaks up, and its ten thousand members scatter wide over the surrounding fields and pasture lands. During courtship the male has a feeble, sketchy music, but his singing is then accompanied with very charming love antics. His circlings about the hen-bird; his numberless advances and retreats, and little soarings above her when his voice swells with importunate passion; his fluttering lapses back to earth, where he lies prone with outspread, tremulous wings, a suppliant at her feet, his languishing voice meanwhile dying down to lispings--all these apt and graceful motions seem to express the very sickness of the heart. But the melody during this emotional period is nothing. After the business of pairing and nest-building is over, his musical displays take a new and finer form. He sits perched on a stalk above the grass, and at intervals soars up forty or fifty yards high; rising, he utters a series of long melodious notes; then he descends in a graceful spiral, the set of the motionless wings giving him the appearance of a slowly-falling parachute; the voice then also falls, the notes coming lower, sweeter, and more expressive until he reaches the surface. After alighting the song continues, the strains becoming longer, thinner, and clearer, until they dwindle to the finest threads of sound and faintest tinklings, as from a cithern touched by fairy fingers. The great charm of the song is in this slow gradation from the somewhat throaty notes emitted by the bird when ascendino-to the excessively attenuated sounds at the close.

In conclusion of this part I shall speak of one species more--the white-banded mocking-bird of Patagonia, which greatly excels all other songsters known to me in the copiousness, variety and brilliant character of its music. Concealed in the foliage this bird will sing by the half-hour, reproducing with miraculous fidelity the more or less melodious set songs of a score of species--a strange and beautiful performance; but wonderful as it seems while it lasts, one almost ceases to admire this mimicking bird-art when the mocker, as if to show by contrast his unapproachable superiority, bursts into his own divine song, uttered with a power, abandon and joyousness resembling, but greatly exceeding, that of the skylark "singing at heaven's gate;" the notes issuing in a continuous torrent; the voice so brilliant and infinitely varied, that if "rivalry and emulation" have as large a place in feathered breasts as some imagine all that hear this surpassing melody might well languish ever after in silent despair.

In a vast majority of the finest musical performances the same notes are uttered in the same order, and after an interval the song is repeated without any variation: and it seems impossible that we could in any other way have such beautiful contrasts and harmonious lights and shades--the whole song, so to speak, like a "melody sweetly played in tune." This seeming impossibility is accomplished in the mocking-bird's song: the notes never come in the same order again and again, but, as if inspired, in a changed order, with variations and new sounds: and here again it has some resemblance to the skylark's song, and might be described as the lark's song with endless variations and brightened and spiritualized in a degree that cannot be imagined.

This mocking-bird is one of those species that accompany music with appropriate motions. And just as its song is, so to speak, inspired and an im-provization, unlike any song the bird has ever uttered, so its motions all have the same character of spontaneity, and follow no order, and yet have a grace and passion and a perfect harmony with the music unparalleled among birds possessing a similar habit. While singing he passes from bush to bush, sometimes delaying a few moments on and at others just touching the summits, and at times sinking out of sight in the foliage: then, in an access of rapture, soaring vertically to a height of a hundred feet, with measured wing-beats, like those of a heron: or, mounting suddenly in a wild, hurried zigzag, then slowly circling downwards, to sit at last with tail outspread fanwise, and vans, glistening white in the sunshine, expanded and vibrating, or waved languidly up and down, with, a motion like that of some broad-winged butterfly at rest on a flower.

I wish now to put this question: What relation that we can see or imagine to the passion of love and the business of courtship, have these dancing and vocal performances in nine cases out of ten? In such cases, for instance, as that of the scissors-tail tyrant-bird, and its pyrotechnic evening displays, when a number of couples leave their nests containing eggs and young to join in a wild aerial dance: the mad exhibitions of ypecahas and ibises, and the jacanas' beautiful exhibition of grouped wings: the triplet dances of the spur-winged lapwing, to perform which two birds already mated are compelled to call in a third bird to complete the set: the harmonious duets of the oven-birds, and the duets and choruses of nearly all the wood-hewers, and the wing-slapping aerial displays of the whistling widgeons--will it be seriously contended that the female of this species makes choice of the male able to administer the most vigorous and artistic slaps?

The believer in the theory would put all these cases lightly aside, to cite that of the male cow-bird practising antics before the female and drawing a wide circle of melody round her; or that of the jet-black, automaton-like, dancing tyrant-bird; and concerning this species he would probably say that the plain-plumaged female went about unseen, critically watching the dancing of different males, to discover the most excellent performer according to the traditional standard. And this was, in substance, what Darwin did. There are many species in which the male, singly or with others, practises antics or sings during the love-season before the female; and when all such cases, or rather those that are most striking and bizarre, are brought together, and when it is gratuitously asserted that the females _do_ choose the males that show off in the best manner or that sing best, a case for sexual selection seems to be made out. How unfair the argument is, based on these carefully selected cases gathered from all regions of the globe, and often not properly reported, is seen when we turn from the book to nature and closely consider the habits and actions of all the species inhabiting any _one_ district. We see then that such cases as those described and made so much of in the _Descent of Man,_ and cases like those mentioned in this chapter, are not essentially different in character, but are manifestations of one instinct, which appears to be almost universal among the animals. The explanation I have to offer lies very much on the surface and is very simple indeed, and, like that of Dr. Wallace with regard [Footnote: It is curious to find that Dr. Wallace's idea about colour has been independently hit upon by Ruskin. Of stones he writes in _Frondes Agrestis_:--"I have often had occasion to allude to the apparent connection of brilliancy of colour with vigour of life and purity of substance. This is pre-eminently the case in the mineral kingdom. The perfection with which the particles of any substance unite in crystallization, corresponds in that kingdom to the vital power in organic nature."] to colour and ornaments covers the whole of the facts. We see that the inferior animals, when the conditions of life are favourable, are subject to periodical fits of gladness affecting them powerfully and standing out in vivid contrast to their ordinary temper. And we know what this feeling is--this periodic intense elation which even civilized man occasionally experiences when in perfect health, more especially when young. There are moments when he is mad with joy, when he cannot keep still, when his impulse is to sing and shout aloud and laugh at nothing, to run and leap and exert himself in some extravagant way. Among the heavier mammalians the feeling is manifested in loud noises, bellowings and screamings, and in lumbering, uncouth motions--throwing up of heels, pretended panics, and ponderous mock battles.

In smaller and livelier animals, with greater celerity and certitude in their motions, the feeling shows itself in more regular and often in more complex ways. Thus, Felidae when young, and, in very agile, sprightly species like the Puma, throughout life, simulate all the

## actions of an animal hunting its prey--sudden, intense excitement of

discovery, concealment, gradual advance, masked by intervening objects, with intervals of watching, when they crouch motionless, the eyes flashing and tail waved from side to side; finally, the rush and spring, when the playfellow is captured, rolled over on his back and worried to imaginary death. Other species of the most diverse kinds, in which voice is greatly developed, join in noisy concerts and choruses; many of the cats may be mentioned, also dogs and foxes, capybaras and other loquacious rodents; and in the howling monkeys this kind of performance rises to the sublime uproar of the tropical forest at eventide.

Birds are more subject to this universal joyous instinct than mammals, and there are times when some species are constantly overflowing with it; and as they are so much freer than mammals, more buoyant and graceful in action, more loquacious, and have voices so much finer, their gladness shows itself in a greater variety of ways, with more regular and beautiful motions, and with melody. But every species, or group of species, has its own inherited form or style of performance; and, however rude and irregular this may be, as in the case of the pretended stampedes and fights of wild cattle, that is the form in which the feeling will always be expressed. If all men, at some exceedingly remote period in their history, had agreed to express the common glad impulse, which they now express in such an infinite variety of ways or do not express at all, by dancing a minuet, and minuet-dancing had at last come to be instinctive, and taken to spontaneously by children at an early period, just as they take to walking "on their hind legs," man's case would be like that of the inferior animals.

I was one day watching a flock of plovers, quietly feeding on the ground, when, in a moment, all the birds were seized by a joyous madness, and each one, after making a vigorous peck at his nearest neighbour, began running wildly about, each trying in passing to peck other birds, while seeking by means of quick doublings to escape being pecked in turn. This species always expresses its glad impulse in the same way; but how different in form is this simple game of touch-who-touch-can from the triplet dances of the spur-winged lapwings, with their drumming music, pompous gestures, and military precision of movement! How different also from the aerial performance of another bird of the same family--the Brazilian stilt--in which one is pursued by the others, mounting upwards in a wild, eccentric flight until they are all but lost to view; and back to earth again, and then, skywards once more; the pursued bird when overtaken giving place to another individual, and the pursuing pack making the air ring with their melodious barking cries! How different again are all these from the aerial pastimes of the snipe, in which the bird, in its violent descent, is able to produce such wonderful, far-reaching sounds with its tail-feathers! The snipe, as a rule, is a solitary bird, and, like the oscillating finch mentioned early in this paper, is content to practise its pastimes without a witness. In the gregarious kinds all perform together: for this feeling, like fear, is eminently contagious, and the sight of one bird mad with joy will quickly make the whole flock mad. There are also species that always live in pairs, like the scissors-tails already mentioned, that periodically assemble in numbers for the purpose of display. The crested screamer, a very large bird, may also be mentioned: male and female sing somewhat harmoniously together, with voices of almost unparalleled power: but these birds also congregate in large numbers, and a thousand couples, or even several thousands, may be assembled together: and, at intervals, both by day and night, all sing in concert, their combined voices producing a thunderous melody which seems to shake the earth. As a rule, however, birds that live always in pairs do not assemble for the purpose of display, but the joyous instinct is expressed by duet-like performances between male and female. Thus, in the three South American Passerine families, the tyrant-birds, wood-hewers, and ant-thrushes, numbering together between eight and nine hundred species, a very large majority appear to have displays of this description.

In my own experience, in cases where the male and female together, or assembled with others, take equal parts in the set displays, the sexes arc similar, or differ little; but where the female takes no part in the displays the superiority of the male in brightness of colour is very marked. One or two instances bearing on this point may be given.

A scarlet-breasted troupial of La Plata perches conspicuously on a tall plant in afield, and at intervals soars up vertically, singing, and, at the highest ascending point, flight and song end in a kind of aerial somersault and vocal flourish at the same moment. Meanwhile, the dull-plumaged female is not seen and not heard: for not even a skulking crake lives in closer seclusion under the herbage--so widely have the sexes diverged in this species. Is the female, then, without an instinct so common r--has she no sudden fits of irrepressible gladness? Doubtless she has them, and manifests them down in her place of concealment in lively chirpings and quick motions--the simple, primitive form in which gladness is expressed in the class of birds. In the various species of the genus Cnipolegus, already mentioned, the difference in the sexes is just as great as in the case of the troupial: the solitary, intensely black, statuesque male has, we have seen, a set and highly fantastic performance; but on more than one occasion I have seen four or five females of one species meet together and have a little simple performance all to themselves--in form a kind of lively mock fight.

It might be objected that when a bird takes its stand and repeats a set finished song at intervals for an hour at a stretch, remaining quietly perched, such a performance appears to be different in character from the irregular and simple displays which are unmistakably caused by a sudden glad impulse. But we are familiar with the truth that in organic nature great things result from small beginnings--a common flower, and our own bony skulls, to say nothing of the matter contained within them, are proofs of it. Only a limited number of species sing in a highly finished manner. Looking at many species, we find every gradation, every shade, from the simple joyous chirp and cry to the most perfect melody. Even in a single branch of the true vocalists we may see it--from the chirping bunting, and noisy but tuneless sparrow, to linnet and goldfinch and canary. Not only do a large majority of species show the singing instinct, or form of display, in a primitive, undeveloped state, but in that state it continues to show itself in the young of many birds in which melody is most highly developed in the adult. And where the development has been solely in the male the female never rises above that early stage; in her lively chirpings and little mock fights and chases, and other simple forms which gladness takes in birds, as well as in her plainer plumage, and absence of ornament, she represents the species at some remote period. And as with song so with antics and all set performances aerial or terrestrial, from those of the whale and the elephant to those of the smallest insect.

Another point remains to be noticed, and that is the greater frequency and fulness in displays of all kinds, including song, during the love season. And here Dr. Wallace's colour and ornament theory helps us to an explanation. At the season of courtship, when the conditions of life are most favourable vitality is at its maximum, and naturally it is then that the proficiency in all kinds of dancing-antics, aerial and terrestrial, appears greatest, and that melody attains its highest perfection. This applies chiefly to birds, but even among birds there are exceptions, as we have seen in the case of the field-finch, Sycalis luteola. The love-excitement is doubtless pleasurable to them, and it takes the form in which keenly pleasurable emotions are habitually expressed, although not infrequently with variations due to the greater intensity of the feeling. In some migrants the males arrive before the females, and no sooner have they recovered from the effects of their journey than they burst out into rapturous singing; these are not love-strains, since the females have not yet arrived, and pairing-time is perhaps a mouth distant; their singing merely expresses their overflowing gladness. The forest at that season is vocal, not only with the fine melody of the true songsters, but with hoarse cawings, piercing cries, shrill duets, noisy choruses, drummings, boomings, trills, wood-tappings--every sound with which different species express the glad impulse; and birds like the parrot that only exert their powerful voices in screamings--because "they can do no other"--then scream their loudest. When courtship begins it has in many cases the effect of increasing the beauty of the performance, giving added sweetness, verve, and brilliance to the song, and freedom and grace to the gestures and motions. But, as I have said, there are exceptions. Thus, some birds that are good melodists at other times sing in a feeble, disjointed manner during courtship. In Patagonia I found that several of the birds with good voices--one a mocking bird--were, like the robin at home, autumn and winter songsters.

The argument has been stated very binefly: but little would be gained by the mere multiplication of instances, since, however many, they would bo selected instances--from a single district, it is true, while those in the _Descent of Man_ were brought together from an immeasurably wider field; but the principle is the same in both cases, and to what I have written it may be objected that, if, instead of twenty-five, I had given a hundred cases, taking them as they came, they might have shown a larger proportion of instances like that of the cow-bird, in which the male has a set performance practised only during the love-season and in the presence of the female.

It is, no doubt, true that all collections of facts relating to animal life present nature to us somewhat as a "fantastic realm"--unavoidably so, in a measure, since the writing would be too bulky, or too dry, or too something inconvenient, if we did not take only the most prominent facts that come before us, remove them from their places, where alone they can be seen in their proper relations to numerous other less prominent facts, and rearrange them patch work-wise to make up our literature. But I am convinced that any student of the subject who will cast aside his books--supposing that they have not already bred a habit in his mind of seeing only "in accordance with verbal statement"--and go directly to nature to note the actions of animals for himself--actions which, in many cases, appear to lose all significance when set down in writing--the result of such independent investigation will be a conviction that conscious sexual selection on the part of the female is not the cause of music and dancing performances in birds, nor of the brighter colours and ornaments that distinguish the male. It is true that the females of some species, both in the vertebrate and insect kingdoms, do exercise a preference; but in a vast majority of species the male takes the female he finds, or that he is able to win from other competitors; and if we go to the reptile class we find that in the ophidian order, which excels in variety and richness of colour, there is no such thing as preferential mating; and if we go to the insect class, we find that in butterflies, which surpass all creatures in their glorious beauty, the female gives herself up to the embrace of the first male that appears, or else is captured by the strongest male, just as she might be by a mantis or some other rapacious insect.

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