EASTERN UNITED STATES. 17 



Phyciodes, Limenitis, Apatura, Paphia, Satyrus, Neo- 

 nympha, and Chionobas may all be distinguished as 

 readily by the egg as by the butterflies." And the 

 same may be said of all the other genera so far as their 

 eggs are known. It has been shown that both the larvae 

 and the eggs of the diiferent species of a genus bear 

 the same relation to each other that the imagines, or per- 

 fect insects, do, and this relation or congruence renders 

 the study of the preparatory stages important, if we 

 would know the true relation that diiferent species bear 

 to one another, or in fact the position of different genera. 

 " Most eggs," Mr. Edwards says, " are green when 

 laid, yellowish, as in Pieris, Colias, and many Papilios, 

 bluish, as in Grapta, grayish, as in Limenitis. Lycsena 

 has a deep-green surface concealed by a white net-work, 

 but which can be peeled off. Parnassius is white; 

 Phollsora Catullus is brown; the Hesperian eggs, as a 

 rule, are white. Many eggs turn red a few hours after 

 deposition, as Colias, Anthocharis, and Melitcea Phaeton. 

 And all these, as well as most other species, change to 

 black before hatching, as the dark larva can be seen 

 through the transparent shell." 



Many eggs are ribbed longitudinally, with transverse 

 stria? between the ribs. In some these ribs run in 

 irregular lines, making an irregular net- work of cells ; 

 in others they are regular, the net-work presenting the 

 appearance of a series of parallelograms, as in Fig. 27. 



In some cases the eggs are not ribbed, but are covered 

 with a series of irregular pits, as in Fig. 75. In some the 

 ribs run from base to apex, varying or not in promi- 

 nence ; in others they gradually diminish before reaching 

 the base, leaving that part perfectly smooth. The egg of 



