3*4 



Microscopical Essays. 



a tent, under which they live, until they have confumed the fur- 

 rounding herbs. They then leave their abodes, and pitch their 

 tents in a more fruitful fpot. 



Many aflbciate together all their lives, others only for a certain 

 period. Thofe who live together proceed from the fame moth 

 •who depofited the eggs near each other, or rather laid them in a 

 heap, forming as it were a kind of neft. Thefe are generally 

 hatched in the fame day, and live together, constituting a new 

 fpecies of republic, in which all are brethren. They often amount 

 to near fix hundred in a family, though they are frequently to be 

 found with only about two hundred. Of thefe. focial caterpillars 

 there are fome fpecies which never quit the fociety while they are 

 in a larva Hate, even placing the chryfalis clofe together. There 

 are other kinds who affociate only for a fhort period. 



Among the vaft variety of infecls which inhabit the oak, there 

 is a fpecies of caterpillar which live feparate till they arrive at. a 

 certain age : they then affemble together, and do not quit each 

 other till they attain their perfect, ft ate. As the number which 

 are thus aflembled is confiderable, the neft is alfo very large. 

 They remain in-doors during the day, not leaving their habita- 

 tion till fun-fet. When they go out, one of the body precedes the 

 reft as a chief, whom they regularly follow : when the leader 

 Hops, the reft do the fame, and wait till it goes on again, before 

 they recommence their march. The firft file generally confifts of 

 a fmgle caterpillar, which are fucceeded by a double file, thefe * 

 by three in a row, which are then followed by files of five, and fo 

 on. They keep exceeding clofe to each other, not leaving any 

 interval either between the ranks, or thofe in each rank: all of 



