^8 INSECT TRANSFORMATIONS. 



goose-quill in the eirn-s of the drinker and other 

 moths which we have dissected*; b\it in the eggs 

 which are deposited in moist places, and in those of 

 spiders, it is extremely thin f- The eg'gs of saw-flies, 

 unts, &c., which grow larger,^ as we shall afterwards 

 show, durinp: the process of hatching', mn^t possess 

 an expansible shell to allow of their enlargement. 

 The yolk and white in the eggs of birds are 

 separated from each other by a very fine membran- 

 ous bag in which each is contained ; but in the 

 eggs of msects, what answers to the yolk consists of 

 distinct minute globules, which float in the white, 

 if we may call it so, for it does not, as we have 

 ascertained, coagulate in boiling water. The eggs 

 of the gypsey-moth {Hypogymna dispor), which 

 we boiled, still continued partly fluid, though the 

 brown matter answering to the yolk was considerably 

 thickened. The portion which does not thicken by 

 boiling most probably forms the first internal fluids 

 of the caterpillar, answering to the blood of quadru- 

 peds. The point where the caterpillar originates, 

 — answering to the scar (Cicatriciila) in the eggs of 

 birds, — we can readily distinguish even by the naked 

 eye in the larger species of eg-gs, as it lies always 

 immediately under the shell*. " Having directed," 

 says the younger Huber, " my close attention to the 

 eggs of ants, I remarked that they were of different 

 sizes, shades, and forms. The smallest were white, 

 opaque, and cylindrical; the largest, transparent, 

 and slightly arched at both ends; while those of 

 a middle size were semi-transparent. On holding 

 them up to the light I observed a sort of white ob- 

 long cloud ', in some, a transparent point might be 

 remarked at the superior extremity; in others, a 

 clear zone above and underneatii the little cloud. The 

 largest presented a single opaque and whitish point 

 *J R. f Kirby and Spence, Intr. S6. 



