Scudder.J 
896 
[February 1, 
little more extensive, the vein beginning to branch a little earlier, 
but on the other hand its branches are almost all simple, and reg- 
ularly distant from each other, while they are somewhat irregular 
in E. carbonaria and one at least is compound. 
This specimen is of particular interest because it preserves 
together, and in a nearly perfect condition, both the front 
wings, enabling a comparison between them which helps better to 
understand how widely variation in the neuration may be looked 
for in the same species. As will be seen from the description 
differences do appear in several places, as for instance in the num- 
ber, forking and consequent approximation of the mediastinal 
nervules, in the basal separation of the scapular branches and the 
very different .character of the first scapular branch, which is sim- 
ply forked on the right side and compound on the left, so that 
five veinlets reach the margin ; or it might perhaps be more cor- 
rectly expressed by saying that on the left side the second branch 
has become amalgamated with the first, while on the right they 
are distinct. There is also a difference in the internomedian area, 
which has, as it were, an extra vein in the left wing by a sudden lon- 
gitudinal start of the main vein where the last branch originates ; 
also a slight difference in the double, instead of single, forking 
of the first internomedian branch on the right side ; and in the 
greater number of anal veins on the right side ; in general the 
left wing has more branches than the right, the only exceptions 
being in the differences last cited. 
The specimen comes from Mazon Creek, Grundy Co., 111., and 
belongs to Mr. J. W. Pike of Vineland, N. J., from whom I 
received it for study. A restoration will be found in Memoirs 
Bost. Soc. Nat. Hist., Vol. III. pi. X. 
