THE EGGS OF INSECTS. 57 



placed downwards, and the narrow end upwards. 

 The secretion used to cement them together is of an 

 oily nature, repellant to water, so that even if the 

 little boat should become accidentally filled, the 

 water quickly retires, as from the feathers of aquatic 

 birds, and the little vessel floats securely till the 

 time for the larvse to escape from their shells arrives. 

 They then issue from the lower part of the egg, 

 and thus at once plunge into the element which is to 

 be their home during the first portion of their active 

 existence. 



The eggs of insects may be said to be invariably 

 hatched without the aid of the warmth or any other 

 influence of the parent, being generally deserted 

 after due precaution to protect them from accidental 

 destruction has been taken. A few rare instances, 

 however, are cited by naturalists, in which insects 

 are said not only to practice incubation, like birds, 

 but even to lead their brood about as a hen does her 

 chickens. This is related of the little obscure insect 

 Pentamata Grisea, of the habits of which De Geer 

 gives a very interesting account. As I have stated 

 above, however, the eggs of insects in general may 

 be said to be hatched without the assistance of the 

 parent, and in most cases without any reference to 

 the temperature, as the larva emerges from its egg- 



