496 [June 



medialy constricted and not widening or covering the space at anal 

 angle. 



From Syneda Howlandii Grote, in which the secondaries are clear, 

 though rather pale red, this species may be readily distinguished, while 

 we apprehend from an additional specimen from Colorado Territory 

 that that species also presents sexual differences of ornamentation in 

 the disposition of the markings of the upper surface of anterior wings. 



To the kindness of Mr. James 0. Treat we are indebted for two 

 alcoholic specimens of the larva of Citheronia sepidcralis Grote and 

 Robinson. 



It is evidently a smaller larva than that of Citheronia regalis Fab. 

 sp., while the general color is paler than that of an alcoholic specimen 

 of the larva of the latter species which we have before us. Structu- 

 rally it appears to us quite identical ; the " horns" on the second, third 

 and fourth segments (counting the " head" as the first) are paler, slen- 

 derer and unicolorous, the lower lateral pair on the third and fourth 

 segments apparently greatly reduced ; the specimens not being quite 

 perfect prevents certain accuracy as to this latter statement. Mr. 

 Treat states that he found the larva in several specimens on the pine, 

 while he was unsuccessful in rearing to the imago state but the single 

 specimen which we have used as the type of the species. We are much 

 interested in obtaining living specimens of the larva of this fine species 

 for full description and comparison with that of its congener, while we 

 are satisfied from what we have seen, that its specific distinctiveness is 

 carried out in all its stages, and we renew our observation that " in 

 this group the generic position of the imago is well indicated in the 

 modifications of larval structure." Proc. Ent. Soc. Philad., April. 

 1865, p. 223. 



