106 



a little irregular ; a terminal black line and fringes as on upper surface ; 

 minute and faint discal dots. 



Expanse, 33 m. m. IlaMtat, Colorado Territory (coll. Tlieo. L. 

 Mead, No. 17). 



The occurrence of tliis genus in America is not noticed before. 

 The hitherto described species are from the Ural Mountains, and 

 have been taken in the evening on flowers according to Lederer. 

 At first sight our species might be taken for Anartas allied to A. 

 luteola, Grote, and the European A. cordigera, but the naked eyes, 

 Hadena-like ornamentation, and the claAV on the fore tibiae quickly 

 distinguishes them. This claw in On. Dayi, is shorter, stouter and 

 blunter compared with a second species, Avhich I describe here, and 

 which equals On. Dayi in expanse, but in which the colors of the 

 primaries above are less distinctly contrasted, while in general 

 appearance the two species resemble each other strongly from the 

 similarity in color of the hind wings. From the yellow-winged 

 European species of Agrotis, sometimes referred under a distinct 

 name to Triphaena, and which the present species casually resemble 

 in the appearance of the hind wings, Oncocnemis differs struc- 

 turally, among other characters, by the non-spinose middle and 

 hind tibiae. 



It is with great pleasure that I name this species after David F. 

 Day, Esq., of this Society, a scientist whose reading is exhaustive, 

 and a friend whose kindness is enduring. 



Oncocnemis Hayesi, Orote, Plate 3, fig. 13. 



<^ . — Eyes naked, strongly lashed ; tibiae all unarmed but with a strong 

 and rather long claw at the extremity of the anterior pair (vide Lederer, 

 Plate 4, fig. 2) ; all the tarsi spinose. In all its structural characters this 

 species agrees with On. Dayi, except that the claw is longer and the eyes 

 and head a little smaller and less prominent. The primaries are dull pulver- 

 ulent yellowish ashen with distinct lines, but not contrasted in their shad- 

 ing. The t. p. line is distinctly continuous, shortly dentate. The ordinary 

 spots are large and rather vague ; the orbicular larger than in On. Dayi. 

 The subterminal line is whitish, powdery, contrasting ; fringes impromi- 

 nently chequered. Hind wings, light, bright yellow, dusky at the base and 

 along the veins ; the dusky scales form an incomplete line crossing the cell 

 over the cross-vein and running to internal margin ; a wide terminal black 



