ANIMAL INTELLIGENCE. 
86 
themselves a brief combing, and then resume their nap, unless, 
indeed, they are satisfied. In watching these movements it was 
quite evident that the Florida soldiers were far less easily dis- 
turbed than their smaller fellows. They slept on stolidly while 
all the others were in agitation around them. Moreover, their 
very appearance, particularly when awaking out of sleep, indi- 
cated the greater sluggishness of their temperament in this 
respect. 
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 mus- 
cular surrender and ea>e. The pleasure which the creatures 
take in being thus 4 combed 9 and 4 sponged 9 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 under- 
stood 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 
