56 BULLETIN 38, UNITED STATES NATIONAL MUSEUM. 



The types, S aud 9 are before me. The difference between the 

 sexes iu the course aud position of t. a. line is remarkable, so much so 

 that did the same variation, in addition to the difference in ground 

 color exist in individuals of the same sex, I should have little hesita- 

 tion in declaring them specifically distinct. There is no other sj^ecies, 

 however, with which this could be easily confused, for none have the 

 same combination of structural characters combined with the same gen- 

 eral style of maculation. Mr. Morrison says the orbicular is sometimes 

 absent, but the presence of the basal and course of the transverse lines 

 will i^revent its confusion with the preceding. 



Pachnobia ferruginoides Smith, sp. nov. 



Rather reddish yellow, hardly ferruginous, veins marked with darker 

 brown. Transverse lines siugle ; t. a. line decidedly oblique outwardly, 

 curved between veins; t. p. line very evenly curved throughout its 

 course. S. t. line marked by a preceding darker shade, its course 

 even, somewhat less oblique than outer margin. A distinct broad 

 rather even transverse shade crosses the median space over reniform. 

 Claviform faintly outlined. Ordinary spots distinctly outlined ; orbicu- 

 lar large, slightly ovate concolorous ; reniform narrow, kidney-shaped, 

 somewhat darkened by the median shade. Secondaries dark ; black- 

 ish fuscous, fringes pale. Beneath powdered with rusty red, a varia- 

 bly distinct common line and discal spot also ferruginous. 



Expands 33-35™'" ; 1.30-1.40 inches. 



Habitat.— Montana, " Black Hills." 



In the S the maculation is less distinct than in the 9 . In the latter 

 sex also there are some elongate scales intermixed in the thoracic vesti- 

 ture, which are entirely wanting in the $ . The species is very dis- 

 tinct from anything heretofore describefl, aud seems in some way to 

 have missed description by me in 1887, when the form was first charac- 

 terized ; how this happened I can not at present say, as I have no oppor- 

 tunity of agian examining my type. 



Pachnobia salicaruni Wlk. 



1857, Wlk.. C. B. Mus. Ilet., xi, 717, Eydrcccia. 

 1882. Grt., 111., Essay, 42, PachnoUa. 



orilliana Grt. 

 1875. Grt., Can. Ent., vii, 154, Pachnobia. 

 1875. Grt., Can. Eut., Vii, 227, pi. 1, f. 8 = claviformis. 

 1882. Grt., 111. Essay, 42, pr. syu. 



claviformis Morr. 



1874. Morr., Pr. Bost. Soc. N. H., 17, 162, AgroHs. 



1875. Morr., Pr. Bost. Soc. N. H., 18, 115, AgroHs. 

 1880. Grt., Bull. Bkln. Ent. Soc, iii, 36 = orilliaim. 

 1882. Grt., 111. Essay, 42 ^= saHcarum. 



Prevailing color red or rust brown, ground color with a yellow tinge. 

 Basal line simple, fine. T. a. line obsoletely geminate, outer portion 



