NORTH AMERICAN LEPIDOPTERA. 213 



ception ; 9 from the subcostal to the costa near tip, sometimes fork- 

 ing near the end of its course giving off thus 10, which, when present, 

 is always very short ; 1 1 from the subcostal usually about the middle ; 

 12 is the costal vein. Secondaries with the cell not extending to the 

 middle of the wing, cross-vein variable ; four always from the inferior 

 angle ; two usually from the middle of the median ; three variable ; 

 five from the cross-vein at varying distances from four, usually closer 

 to four than six ; six and seven together from the end of the sub- 

 costal ; costal vein variable, depending somewhat on the wing shape. 



This subfamily is very distinctly sejiai'ated in its entirety from the 

 rest of the Sphinges, forming a division equal in value to all the rest. 

 In its division I have met with considerable difficulty, less because 

 there were no characters, but because there were so many that a 

 genus might almost be based on every species. Indeed, this has been 

 done, except for mijops, which I believe is not a generic type. Astylus 

 and mijops, in fact, are the only species strictly identical in structure, 

 except in the genitalia. The other extreme — lumping everything 

 under Smerinthm seemed equally undesirable, and it was not an easy 

 task to strike the correct mean. Prior writers seem to have had no 

 definite basis for their subdivisions, a number of si)ecies being first 

 associated in one way then in another, and finally separated alto- 

 gether. The genital structure of tiie male has here again given 

 valuable hints, and I believe the present arrangement as satisfactory 

 as can be easily made. I have excluded the species of Elle}na from 

 the subfamily contrary to my previously cxjjressed opinions, having 

 convinced myself tiiat Mi'. Grote was more nearly right in consider- 

 ing them degraded SpJiinguuv. Though liaving an aborted tongue, 

 the wing form and habitus, as well as the genitalia, are more .Sphingid 

 than otherwise. 



I head the species with Trijjfogon, whicii contains our largest spe- 

 cies, and has the fore tibiie armed with a long, stout claw. The 

 genital structure is unique and described in its proper i)lace. There 

 is but a single species. I follow this by Smerlntlm.-<, which contains 

 three species agreeing in type of genital structure, in the genei'al body 

 form, in habitus and in pattern of maculation. In all the dor- 

 sum of thorax between the patagige is deep brown, the primaries 

 have an outwardly angulated band ov line at basal third, and the 

 secondaries have the ocellus black centred and connected by a black 

 spur, with the anal angle ; the costal margin is straight. In an- 

 teunal structure these species difier greatly, and to a less extent in 



