NORTH AMERICAN LEPIDOPTERA. 165 



As in the other characters the genital structure is variable. The 

 supra-anal plate and hooks have, essentially, a similar form, the hook 

 being rather long and curved, almost meeting the inferior process, 

 which is stouter, but much shorter ; the side pieces and claspers vary, 

 so that it will be necessary to describe them in detail with each 

 species. 



The characters that hold together these species are the prominent 

 head, large eyes and heavy build. These give them a distinctive 

 appearance, the eyes especially, being much larger and more promi- 

 nent than in the succeeding genera. 



Celeus is a heavier, more robust form than either of the others, 

 with wider wings and more even outer margin and heavier tibial 

 armature. The secondaries have the median lines very distinct and 

 strongly dentate. 



Carolina is intermediate between this and the other species as well 

 in wing shape as in the armature of fore legs. It is a decidedly 

 slighter insect. The secondaries have the two median lines much less 

 distinct, obscured by a dusky shade and not distinctly dentate on 

 the veins. 



Rusiiea differs at once by the deep umber brown color, with tlie 

 prominent white maculation. It is a stouter insect than earollnu, 

 but not so heavy as celeus. All these have the sides of abdomen 

 maculate with yellow. 



Cingulata differs from all the others in the rose red maculation of 

 the abdomen and secondaries. In habitus it is much like rustlca. 



It will be seen that the genus is not the most compact, yet the 

 species form a rather distinctive group, which has been almost uni- 

 versally recognized by authors, though but the least satisfactory 

 characters were relied upon or discovered ; most of them were con- 

 tent to recognize the genus without troubling themselves to define it. 



I have used Burmeister's term Protoparce, following Butler in this 

 respect. Hiibner's term is not one expressing a distinct idea, and 

 the three American species now referred as congeneric were placed 

 in three distinct co'dl by him. 



I*, celeus Hiib., Saumil. ii, pi. 377, Phlegethont'ms ; Edw.,* Pr. Cal. Ac. Sci. vi. 

 92, Macrosila; Butl., Trans. Zool. Soc. Loud. ix. G07, Protoparce; Behr.,* 

 Pap. ii, 3; Grt., Pap. ii, 99; Feriiald,* Sphing. 33, Phlegethontius ; Grt., Hawk 

 Moths 40, Phlegethontius. 



