ON ARACHNIDA. 451 



ludinally by blackish bands. Its aperture is hermetically 

 sealed by a silken plug. This envelope contains a second, 

 the tissue of which is still softer : it is a true down, which 

 preserves the eggs from any accident. Almost all the cocoons 

 of the araneides are equally composed of two kinds of silk, 

 the interior of which is finer, and softer to the touch. 



The insects which do not live in society, as soon as their 

 eggs are laid, give themselves no further care touching their 

 posterity. Many of the araneides, on the contrary, guard 

 with the utmost vigilance the fruit of their anaours ; some even 

 carry between their feet their eggs, shut up in the cocoon. 

 When the young ones are first disclosed, they attach them- 

 selves on the back of their mother. All the eggs are of a 

 round form, white, or yellowish white. Those of many species 

 exclude fifteen or twenty days after they have been laid ; 

 others pass the winter, and do not exclude until spring. Some 

 days before the young issues forth from them, the pellicle, 

 which is very slender, changes form, and suffers all the parts 

 of the insect to appear. 



As soon as the young araneides which make webs have left 

 the egg, they begin to spin directly. The female lycosse tear 

 open the cocoon, which encloses their young, to give them a 

 greater facility of coming forth, at the moment in which they 

 should quit it. These mount on the back of the mother, who 

 carries them along with her; and when she finds an insect, 

 she shares it with them. The araneides, in general, exhibit 

 a very great attachment to their young. All the young 

 araneides live, as it were, in society, until the first moulting : 

 they then separate, and become mutual enemies. They grow 

 very much in their youth, and in augmenting in volume, tbey 

 change their skin. It is believed that they quit it three times 

 before they are in a state for reproduction. Their life is more 

 or less long. Audebert brought one up, and preserved it for 

 several years. 



G 0-2 



