THE "displays" made by male birds and by some other animals which lead to the "fascination" of the females, and apparently to a condition similar to that which is called "hypnotic" in man, are very remarkable. One is tempted to say that these "displays" are made "for the purpose" of fascinating the female. But though that would be correct in describing similar proceedings on the part of a human "gallant," it is not strictly so in the case of animals, any more than it is true that a bird grows its fine plumage "for the purpose" of attracting the female. The male bird finds itself provided with fine feathers, and has probably a brief conscious pleasure in the fact, just as it has in singing, but it has, of course, no control over the growth of its feathers, nor conscious purpose in their production. Similarly, it has no knowledge or consciousness of a purpose in the antics of "display," nor in singing its melodious song, though certainly it is gratified, and has pleasurable sensations in the instinctive performances which it finds itself going through. The great French entomologist, Fabre, who has more minutely and thoroughly studied the wonderful proceedings of insects in regard to these matters and others, such as nest building, care and provision for young, deliberately says, "Ils ne savent rien de rien"—they know nothing about anything! And that is true with only small exception about even the highest animals until we come to man. Some of the higher animals have a brief and fleeting "consciousness" of what they are doing, and some of the hairy quadrupeds nearest to man have the power of "recollecting"; that is to say, have in a small degree conscious memory, and actually do reason and make use of their memory of their own individual experience to a very small and limited degree.

It is only in man that the power of reasoning—the conscious use of memory, of deciding on this or that course of action by a conscious appeal to the record of the individual's experience inscribed in the substance of the brain—becomes a regular and constant procedure. And in the lowest races of man—as, for instance, the Australian "black fellows"—this power is much less developed than in higher races, owing to the feebleness of their memory. Just as a little child or an old man recognizes the fact that his memory is bad, so does the Australian native confess to the white man that he cannot remember, and marvels at the memory of the white man, who, he says, can see both what is behind and what is to come.

"Displays" are often made by birds which have no very brilliant colours. The ruff—a bird of agreeable but sombre plumage—spreads out a ruff of feathers which grows round his neck in the breeding season and stands in a prominent position alone on the open ground with his head facing downwards and his long beak nearly touching the ground. These birds are to be seen behaving in this way at the Zoological Gardens in London. When thus posed they have a comical appearance of being absorbed in profound thought. Suddenly, after posing for perhaps ten minutes or more immovably in this attitude, the ruff starts into life, running in a wide circle and spreading his wings, and then as suddenly relapses into his pose, with downcast eyes and beak touching the ground. This, it appears, is all a challenge to any other ruff who ventures near him, and often results in a fight with another individual who is offended by his "swagger" and attacks him. It also is an invitation and attraction to the female or "reeve" who is on the look out for a mate.

The display of the bustard, though his feathers are only light brown and white, is a very strange and arresting performance. In ordinary circumstances his feathers are nicely smoothed down, and he looks neat and fit. But at the breeding season he behaves like Malvolio when he wore cross-garters to please his lady. He approaches two or three females who are quietly feeding, and throwing his head back and his chest forward, swelling his neck out with inspired air and reflecting his tail feathers inside out (so to speak) over his back, he makes the most extraordinary havoc of his previously neat costume. The feathers are made to stand up and reflected backwards in groups, and show their underlying white surfaces round the head, on the chest, and on the wings and back, so that he suggests the appearance of a portly old gentleman, in full evening dress, the worse for liquor, his high collar unbuttoned and flapping, his short "front" bulging and loose, whilst he maintains all the time a pompous and dignified pose strangely inconsistent with his disordered costume and hesitating gait. As he struts and poses the lady bustards, though intensely interested in his strange behaviour, make no sign, and continue pecking for food, as who should say with Beatrice, "I wonder that you will still be talking, Signior Benedick: nobody marks you." After enduring this snubbing on several occasions and doggedly continuing to display his antics, the persistent bustard reaps his reward. One among the dissembling females can no longer keep up the pretence of indifference, and suddenly runs off, inviting him to follow her! The same general scheme of play is seen in the case of the peacock, who spreads his magnificent "train" around his head and neck (not to be confused with his tail, as it often is); in the case of the turkey, bubblyjock, or gobble-cock, who struts and shows off his coloured wattles and fine feathers; in that of the domestic fowl, who raises his head and neck, crows, and has a pretty trick of scraping the ground with his wing. Many other birds perform special antics suited to the display of their special plumage. Among the most varied and remarkable are those of the Birds of Paradise, which drop through the air, hang upside down on tree twigs, and pose themselves variously (often warbling the while seductive notes) according to the particular beauties which distinguish each species. Cranes and some other birds dance in groups at the mating season—really dance, making steps and jumps with the legs and movements of the wings—in rhythm.

Reptiles do only a little in the way of display. The male newt gets a crest in the spring like the wanton lapwing of Tennyson, and a splendid orange-red colour on the belly. Male fishes often develop "display" colours at the breeding season, and it is a mistake to suppose that their eyes and brains are not sensitive to colour. We have a familiar instance in the male of our common little stickleback, who, in early summer, builds, in his native pond, his nest of fragments of weed cemented together, with a wide entrance and a back door. He then becomes brilliant blood-red on the belly (he was white before) and dark green on the back, and swims about near the nest, and has an occasional fight with a competitive neighbour, whilst hustling and shepherding any female stickleback he may meet so as to make her enter it. She enters it alone, and lays an egg, or, perhaps, two or three, and then goes out by the back-door! The male, well pleased, at once goes into the nest, fertilizes the eggs, and swims out again to get another contribution to his future family. After several females have thus deposited eggs in his nest, and he has fertilized them, he keeps guard for many days whilst the young are developing. Even when they are hatched he is in constant attendance on them, for there is danger of their being eaten—not by other males, who are as busy as he is, but by the emancipated females, who neither build the nest nor care for the young, but just lay an egg here and an egg there when invited, and pursue a selfish life of amusement and voracious feeding.

It is still doubtful how far male insects of the true six-legged group appeal to the females by colour-display, even when they are brightly coloured, or in other ways than by perfumes (which they do very generally), but among the spiders there are some kinds (not common ones) in which the males have on the front of the body one or two extraordinarily brilliant spots of colour (red, apple-green, or yellow). The male moves round the female in courtship, and poses himself in most curious attitudes, so as to exhibit the brilliant colour to her; forcing it, as it were, on her attention. In other species of spiders the male dances and circles round the female, making curious and definite antics. Some spiders also have rasp-like organs, with which they can make a kind of singing note, which appears to fascinate the other sex. The vibration of a tuning-fork will cause some spiders to dance! In most spiders the female is much larger than the male—in some cases, ten times as large—and the approach of the male to the female is a dangerous business for him, for usually after his embrace she turns on him, kills him, and eats him. This is almost a unique case amongst animals (though ancient legends tell of princesses of similar ferocity), and curiously enough is not invariable among all species of spider. In some the males and females are quite friendly. The ogre-like habit of female spiders is not so injurious a thing as it may appear. For the most nourishing food is thus afforded to the female who has to ripen her eggs, and take care of her young, whilst, if the male escapes, it appears that he is short-lived and very soon dies. This cannibal tendency is very strongly developed also in the allied group, the scorpions. Two hundred scorpions were left in a cage in the South of France, whilst the naturalist (Maupertuis) who had placed them there was obliged to go to Paris. On his return he found one large, very plump and active scorpion in the box, surrounded by legs and hard bits of the bodies of the rest. The survivor was in the position of Gilbert's ancient mariner, who said that he was "the cook and the mate, and the captain's boy and the crew of the Nancy Bell." Scorpions do not perform any courtship display. The males and females are of equal size, and dance together, holding one another by their large claws, before mating and retiring into a burrow.

Cuttle-fishes, squids, and the octopus—called Cephalopods—were considered by Aristotle to be the spiders of the sea. It is curious how they not only have a superficial resemblance of form to spiders, but in some habits are like them, though the Cephalopods are molluscs allied to snails and mussels, and are quite unlike spiders in deeper structure and remote from the whole group of hard-skinned, jointed-legged animals such as crustaceans, spiders, and insects. I once had the chance to see a male octopus "displaying" to a female in one of the tanks of the aquarium at Naples. There were a male and a female already living there when we introduced from another tank a second male, which had just destroyed and fed upon a large lobster, who had himself, with no evil purpose, crushed the head of a Mediterranean turtle foolishly placed by that animal between the open fingers of the lobster's big nippers. The new arrival promptly drove the earlier tenant octopus out of the tank. He pursued his rival round and round with great rapidity until the latter leapt from the surface of the water (by a violent contraction of the mantle) and escaped into the adjacent tank. Then the triumphant intruder approached the female—floods of changing colour, reddish-brown, purple, and yellow, passing over the surface of his body—and commenced an extraordinary display with his eight long sucker-bearing arms. He made these wind into close-set flat spirals and again unwind and gracefully trail in the water, when they immediately wound up again in spiral coils. The female watched this proceeding for more than an hour, and then they embraced. I could not follow any further details, but a few days after this the female piled up a number of stones, so as to make a nest in shape like a shallow basin. We enticed the male into a net and placed him in another tank, so that he should not be able to molest the female or to devour her offspring, which he would do if he had the chance. Then the female laid her eggs—minute oval, transparent bodies, each with a long stalk and all joined on to a common branching stem: the whole resembled a head of millet seed. The female tended her eggs by continually pumping a stream of water over them, and could not be driven from them. She fought savagely and heroically in their defence. But I succeeded in enticing her into a net by aid of a toothsome crab, and then took a few—only a few—of the cherished eggs, and replaced their mother in the tank, where she at once resumed the "incubation" of her eggs. For it is an "incubation," although one in which oxygenated water, and not warmth, is the accompaniment of the sitting of the "hen." I was able to watch the development of the young within the transparent eggs, which I kept in a stream of fresh sea-water, and I published a short account of what was novel in the growth of these embryos. It had not been studied previously, nor have I seen any later account of the development of octopus. The true cuttle-fish, with the hard oblong shell sunk in the back, lays each egg in a dark leathery shell. They look like small grapes, and are left, thus protected, to their fate. They have been studied, both before I obtained octopus eggs and since, in great detail. The "squid" embeds her eggs, many together, in bunches of long fingers of colourless jelly. Only the octopus and the argonaut, among Cephalopods, are known to give maternal care and incubation to their eggs.