1910] Barnes and McDunnough—Sphingide of North America 201 
(68) H. gracilis G. & R. INANE 
(69) H. diffinis Bdv. 
(a) diffinis diffinis Bdv. Atlantic States. 
(a’) f. vern. tenuis Grt. 
(b’) f. est. diffinis Bdv. 
(c’) f. est. axillaris G. & R. 
(b) diffinis aethra Stkr. Me., Montreal, Que., Nipigon, Ont. 
(c) diffinis ariadne n. nov. Colo., Man. 
syn. senta R. & J. (non Strecker). 
(d) diffinis thetis Bdv. Pacific Subregion. 
(d’) f. thetis Bdv. Cal! 
syn. palpalis Grt. 
(e’) f. cynoglossum Edw. Cale 
(f’) f. rubens Hy. Edw. Ore., B. C., Ariz., Utah. 
We have been obliged to differ from Rothschild & Jordan in 
the above arrangement as an examination of Strecker’s types 
has convinced us that his two species ethra and senta have never 
been properly recognized. In Group A., diffinis diffinis, we have 
followed the revision; the various seasonal forms of this eastern 
race are well known; tenuis, with non-dentate border of fore wing, 
represents the spring brood, whilst diffints and azillaris, which 
only differ from each other in the more or less prominent denta- 
tion of the border on primaries, constitute two summer forms. 
Aithra Stkr. has been placed by Rothschild & Jordan as a syno- 
nym of avillaris G. &. R., due probably to a statement of Smyth’s 
(Ent. News, 1900, p. 585) that he has bred the form e@thra from 
tenuis ova. While we recognize the fact that some specimens 
of tenuis tend to lose the dark abdominal band and develop a 
red apical spot, we consider the true ethra well distinct from such 
specimens. The type specimen, which we have examined, is from 
Montreal, Que.; besides this there are in the Strecker Coll. sev- 
eral very perfect specimens from Bangor, Me., and in Coll. Barnes 
5 oo, 12 from Nepigon, Ont. These all agree exactly with 
one another and differ from other eastern forms of diffinis in the 
roughness of the body squamation. The yellow of thorax and 
abdomen is not the pale yellow of diffinis or tenwis but rather an 
orange-brown, bordered narrowly with a pale yellow extending 
along patagia and sides of abdomen; the red apical patch is 
sharply defined and not continued along outer margin; the red 
of anal angle on secondaries is bright and the base of primaries 
