I'M", 



Length of body, &, 0.44, 9, 0.60; of fore wing, <?, 0.54, 9,0.64; 

 expanse of wings, 1.25 inches. 



Denver City, Colo., 1 $ June 3, 9 June 27, in the Rocky Mountains 

 of Colorado (T. L. Mead). 



The occurrence of this genus is of much interest, as il constitutes a new 

 link between the Pacific Slates and European fauna. The male of this 

 species is mueh smaller than the female, with the hind wings especially 

 much elongated. The outer row of black dots is wanting in my single 

 specimen. 



LlTHOSTEGE rotundata Packard. Plate 9, iig. 29. 

 Lithoatege rotundata Pack., Sixth Rep. Peab. Acad. Sc, :!'.), 1874. 



2 <?. — This is a much smaller species than L. triseriata, and the hind 

 wings are shorter and much more rounded. The markings are very similar. 

 Head and palpi with black and white scales, the palpi stout. The fore tibial 

 spines stout. Fore wing with the same markings as in L. triseriata, but with 

 the outer sub-marginal white line narrower and more distinct. The third row 

 of black dots wanting, as in the male of t he Colorado species. Fringe and 

 hind wings and under surface as in the Colorado species. A dark apical 

 oblique streak on the fore wing, not present in L. triseriata. 



Length of body, 0.40; of tore wing, 0.4!) ; expanse of wings, 1.00 inch. 



San Diego, Cal. (Gr. R. Crotch, Mus. Comp. Zool.). 



This species, while closely resembling L. triseriata, resembles the 

 European L. farinata more closely in the peculiar shape of the hind wings 

 than the Colorado species. The fore wings are a little more broadly triangu- 

 lar than in L. triseriata. 



Subfamily OPEEOPHTEEIN^ Packard. 



Male — The single genus of this group is so different from the Larentina 

 on the one hand, and the Fidoninee on the other, that it seems warrantable to 

 suggesl a new subfamily for it. It certainly has no immediate affinities with 

 the Larentince With Hybernia and A?tisopteryx, the affinities are remote. 

 The head is short and small; the body, especially the thorax, unusually slen- 

 der. The palpi are unusually weak and short, not reaching out as far as the 

 front. The front of the head is nearly as wide as long. Male antenna 1 

 densely ciliated. The wings are large and broad. Fore wings with the costa 



