The ordinary duration of sleep MacCook takes to be about three hours.
Ants, like many other insects, are in the habit of cleaning themselves, being, like them, provided by nature with combs and brushes, &c., for the purpose. But, unlike other insects, several species of ants are also in the habit of assisting each other in the performance of their toilet. The author last quoted gives the following account of this process in the genus Atta:—
We take a couple; the cleanser has begun at the face, which is licked thoroughly, even the mandibles being cared for, they being held apart for convenient manipulation. From the face the cleanser passes to the thorax, thence to the haunch, and so along the first leg, along the second and third in the same manner, around to the abdomen, and thence up the other side of the ant to the head. A third ant approaches and joins in the friendly task, but soon abandons the field to the original cleanser. The attitude of the cleansed all this while is one of intense satisfaction, quite resembling that of a family dog when one is scratching the back of his neck. The insect stretches out her limbs, and, as her friend takes them successively into hand, yields them limp and supple to her manipulation; she rolls gently over upon her side, even quite over upon her back, and with all her limbs relaxed presents a perfect picture of muscular surrender and ease. The pleasure which the creatures take in being thus 'combed' and 'sponged' is really enjoyable to the observer. I have seen an ant kneel down before another and thrust forward the head, drooping, quite under the face, and lie there motionless, thus expressing, as plainly as sign-language could, her desire to be cleansed. I at once understood the gesture, and so did the supplicated ant, for she at once went to work. If analogies in nature-studies were not so apt to be misleading, one might venture to suggest that our insect friends are thus in possession of a modified sort of Emmetonian Turkish bath.
The acrobatic skill of these ants, which has often furnished me amusement, and which I shall yet further illustrate, was fully shown one morning in these offices of ablution. The formicary was taken from the study, where the air had become chilled, and placed in an adjoining chamber upon the hearth, before an open-grate fire. The genial warmth was soon diffused throughout the nest, and aroused its occupants to unusual activity. A tuft of grass in the centre of the box was presently covered with them. They climbed to the very top of the spires, turned round and round, hanging by their paws, not unlike gymnasts performing upon a turning-bar. They hung or clung in various positions, grasping the grass blade with the third and fourth pairs of legs, which were spread out at length, cleansing their heads with the fore-legs or bending underneath to comb and lick the abdomen. Among these ants were several pairs, in one case a triplet, engaged in the cleansing operation just described. The cleanser clung to the grass, having a fore-leg on one side and a hind leg on the other side of the stem, stretched out at full length, while the cleansed hung in a like position below, and reached over and up, submitting herself to the pleasant process. As the progress of the act required a change of posture on the part of both insects, it was made with the utmost agility.
Similarly, Bates thus describes the cleansing process in another genus of ants (Ecitons):—
Here and there an ant was seen stretching forth first one leg and then another, to be brushed and washed by one or more of its comrades, who performed the task by passing the limb between the jaws and tongue, finishing by giving the antennæ a friendly wipe.
Habits of Play and Leisure.—The life of ants is not all work, or, at least, is not so in all species; for in some species, at any rate, periods of recreation are habitually indulged in.
Büchner('Geistesleben der Thiere,' p. 163) gives the following abstract of Huber's celebrated observations in this connection:—
It was of the pratensis that Huber wrote the observations touching its gymnastic sports which became so famous. He saw these ants on a fine day assembled on the surface of their nest, and behaving in a way that he could only explain as simulating festival sports or other games. They raised themselves on their hind legs, embraced each other with their fore-legs, seized each other by the antennæ, feet, or mandibles, and wrestled—but all in friendliest fashion. They then let go, ran after each other, and played hide-and-seek. When one was victorious, it seized all the others in the ring, and tumbled them over like ninepins.
This account of Huber's found its way into many popular books, but in spite of its clearness won little credence from the reading public. 'I found it hard to believe Huber's observation,' writes Forel, 'in spite of its exactness, until I myself had seen the same.' A colony of the pratensis several times gave him the opportunity when he approached it carefully. The players caught each other by the feet or jaws, rolled over each other on the ground like boys playing, pulled each other inside the entrances of their nest, only to come out again, and so on. All this was done without bad temper, or any spurting of poison, and it was clear that all the rivalry was friendly. The least breath from the side of the observer was enough to put an end to the games. 'I understand,' continues Forel, 'that the affair must seem marvellous to those who have not seen it, especially when we remember that sexual attraction can here play no part.'
MacCook also gives an account of habits of play as indulged in among ants of the other Hemisphere:—
At one formicary half a dozen or more young queens were out at the same time. They would climb up a large pebble near the gate, face the wind, and assume a rampant posture. Several having ascended the stone at one time, there ensued a little playful passage-at-arms as to position. They nipped each other gently with the mandibles, and chased one another from favourite spots. They, however, never nipped the workers. These latter evidently kept a watch upon the sportive princesses, occasionally saluted them with their antennæ in the usual way, or touched them at the abdomen, but apparently allowed them full liberty of action.
As to leisure, Bates writes:—
The life of these Ecitons is not all work, for I frequently saw them very leisurely employed in a way that looked like recreation. When this happened the place was always a sunny nook in the forest. The main column of the army and the branch columns, at these times, were in their ordinary relative positions; but instead of pressing forward eagerly and plundering right and left, they seemed to have been all smitten with a sudden fit of laziness. Some were walking sternly about, others were brushing their antennæ with their fore-feet; but the drollest sight was their cleaning each other. [Here follows the above-quoted passage.] The actions of these ants looked like simple indulgence in idle amusement. . . . . It is probable that these hours of relaxation and cleaning may be indispensable to the effective performance of their harder burdens; but whilst looking at them, the conclusion that the ants were engaged merely in play was irresistible.[31]
Funereal Habits.—In another connection it has already been stated that Sir John Lubbock found his ants to be very careful in disposing of the dead bodies of their comrades. This habit seems to be pretty general among many species of ants, and is no doubt due to sanitary requirements, thus becoming developed as a beneficial instinct by natural selection. The funereal habits of the agricultural ant are thus related by MacCook:[32]—
There is nothing which is apt to awaken deeper interest in the life-history of ants than what may properly be called their funereal habits. All species whose manners I have closely observed are quite alike in their mode of caring for their own dead, and for the dry carcasses of aliens. The former they appear to treat with some degree