176 



PTILOTA. 



ceptacle for the egg which is deposited immediately after- 

 wards. 



The colour of insects' eggs varies very considerably, al- 

 though white, yellow, and green are the more prevalent 

 tints ; orange, red, brown, and black, with all the interme- 

 diate shades, are to be found, as well as blue ; and others are 

 banded with pale circles, and that of the pine lappet moths 

 is blue, with three brown zones. The colours of eggs are, 

 however, subject to change as the inclosed larva approaches 

 the period of its escape, this being o\%'ing chiefly to the 

 change of colour undergone by the latter being visible 

 through the slender coating of the egg. 



In many species the eggs are deposited singly ; in others, 

 however, they are discharged en masse, of which the most 

 remarkable instance occurs in the cockroaches 

 {Blattce), the egg pouch of which is here fi- 

 gured. Others again arrange them symmetri- 

 cally (as in the cyhndrical pointed eggs of the 

 Semblis lutea, fig. 6), and others mclose them 

 m a mass of gluten, especially those species 

 ^''Ifa'tta!' °^ which inhabit the water in the larva state : 

 many species employ a gummy matter to at- 

 tach them firmly to the substances on which they are 

 placed ; whilst some (as the yellow-tail moth, Arctia chry- 

 sorrhcea) wTap them in a coating of down (fig. 7), which 

 they pull off" their ovra bodies by the assistance of an appa- 

 ratus fitted for that pui-pose ; and the lackey moth {Lasio- 



