ESCAPE OF ANTS. 289 



instructed by a heavenly Ruler and Guide to 

 give help to the prisoners, and to secure their 

 egress. But how do these indefatigable attend- 

 ants ascertain precisely the moment when their 

 aid is required ? The insect within has no power 

 of voice to cry out for help, nor those without, 

 in all probability, the faculty of hearing, if it 

 could do so. It seems probable that they are 

 acquainted with it from some slight movements 

 which take place within, which they ascertain 

 by means of their antennae. Whatever it be, 

 the attendants never interfere at a wrong time. 

 Their manner of proceeding is beautifully described 

 in the following words of this author : " Several 

 males and females lay in their envelopes in one of 

 the largest cavities of my glazed ant-hill. The 

 labourer -ants assembled together, and appeared to 

 be in continual motion around them. I noticed 

 three or four mounted upon one of these cocoons, 

 endeavouring to open it with their teeth, at that 

 extremity answering to the head of the pupa. 

 They began to thin it by tearing away some 

 threads of silk where they wished to pierce it, and 

 at length by dint of pinching and biting this tissue, 

 so extremely difficult to 'break, they formed in it a 

 u 



