322 Insects' Bggs. 



purpose, she bores a hole in the bark in which to deposit 

 them. Not infrequently the interior of fruit or grain, or even 

 a dung-heap is selected, and some few commit their store to 

 water, there to await the heat of the summer sun to hatch the 

 brood. 



Their defence against cold, and atmospheric changes con- 

 sist in coating the inside with a varnish-like substance, while 

 the outside is often covered over with a denser material, as 

 portions of vegetable fibre and the hairs or feathers from the 

 body of the insect, which, together with the leaf on which the 

 eggs are laid, form groups of tiny nests. Others form stronger 

 and more durable receptacles. The female cock-roach con- 

 structs a strong horny bag, or purse, in which having deposited 

 her eggs, she carefully carries it about with her. The coccus 

 converts her whole body into a shield or covering for her eggs, 

 so thoughtful does she appear for the future safety of her 

 brood. As a general rule, the female insect having deposited 

 her full number of eggs, leaves them to be hatched by the heat 

 of the sun, which may be accomplished in a few days, or not 

 until the following spring, as is the case with the eggs of the 

 silkworm, and all those laid late in the summer or autumn. 

 The number' of eggs produced by different species is very 

 varied, some depositing only two, while others, and by far 

 the largest number, lay them by hundreds. The ant is said to 

 lay from thirty to forty thousand in a year. The queen-bee, 

 fifty thousand; but I believe the ordinary number is much 

 below this. The silkworm moth mostly lays about five hun- 

 dred eggs. The goat-moth, about a thousand, and the tiger- 

 moth some fifteen hundred, arranged with the most uniform 

 and symmetrical order. Insects' eggs bear great extremes of 

 temperature without losing their vitality; want of air and 

 light appear to be far more speedily detrimental in this respect 

 than the extremes of heat or cold. I have exposed silkworm's 

 eggs to severe frosts, and also plunged them into scalding- 

 water, without in the least affecting them, either for good or 

 evil. Several genera of moths with wonderful instinct, cover 

 their eggs with soft vegetable materials; and some, it is 

 asserted, pluck the hair and feathers from their bodies for the 

 same purpose. A writer states, I think, without sustaining the 

 statement by sufficient evidence, that moths use a pair of pin- 

 cers, placed at one extremity of the body, for plucking out 

 their hairs to cover their eggs ; but this would scarcely seem 

 to be needful, since the eggs are nearly always deposited in 

 groups, and securely fastened up in the leaf on which they 

 have been deposited, so that frequently it requires some force 

 to separate the bundle, and expose them to view. 



Some of the Coleopterous insects resort to curious and inge- 



