ANTS — SLEEP AND CLEANLINESS. 
85 
arouse the sleeper by a sharp touch of the quill. She stretches 
out her head, then her legs, which she also shakes, steps nearer 
to the light, and* begins to cleanse herself in the manner already 
described. This act invariably follows the waking of ants from 
sleep. The above description applies to the general habit of 
somnolence as observed upon the two named species of harvest- 
ing ants for nearly four months. I have often applied the 
quill, and even the point of a lead pencil, to the sleeping Flo- 
ridians without breaking their slumber. There are some other 
details which have not appeared in the behaviour of the indi- 
vidual just put under observation. 
Thus, I have several times seen the ants ( Crudelis ) yawning 
after awaking. I use this word for lack of one w T hich more 
accurately expresses the behaviour. The action is very like 
that of the human animal ; the mandibles are thrown open 
with the peculiar muscular strain which is familiar to all 
readers ; the tongue also is sometimes thrust out, and the limbs 
stretched with the appearance, at least, of that tension which 
accompanies the yawn in the genus homo. During sleep the 
antennae have a gentle, quivering, apparently involuntary mo- 
tion, which seemed to me, at times, to have the regularity of 
breathing. I also often noted an occasional regular lifting up 
and setting down of the fore-feet, one leg after another, with 
almost a rhythmic motion. 
The length of time during which sleep is prolonged appears 
to vary according to circumstances and, perhaps, organism. 
The large head-soldiers of the Floridian harvesters appear to 
have a more sluggish nature than the smaller workers. Their 
sleep is longer and heavier. The former fact the watch readily 
determined. The latter appeared from the greater stolidity of 
the creatures under disturbance. While the ants of one group 
are taking sleep others may be busy at work, and these stalk 
among and over the sleepers, jostling them quite vigorously at 
times. Again, new members occasionally join the group, and, 
in their desire to get close up to the heat and light, crowd their 
drowsy comrades aside. I have seen ants who had been at 
work in the galleries drop their pellets, push thus into the 
cluster, and presently be apparently sound asleep. This rough 
treatment is invariably received with perfect good humour, as 
are like jostlings when the ants are awake. I have never seen 
the slightest iisplay of anger or attempt to resent disturbance 
even under these circumstances, so. peculiarly calculated to ex- 
cite the utmost irritation in men. But of course some of the 
sleepers are aroused. They change position a little, or give 
