ME. A. G. BUTLEU ON THE UEAPTEETGIBJ5. 195 



On the Moths of the Family Urapterygidae ia the Collection of 



the British Museum. By Aethur Gr. Butler, F.L.S., F.Z.S. 

 [Read March 15, 1883-] 

 (Plate IX.) 

 The family of Geometrites founded by Gruenee under this name 

 can only arbitrarily be separated from the Eunomidse. Dr. 

 Packard says : — " The fact that genera so closely allied as Dre- 

 panodes and Eutrafela are placed separately in the families 

 ' Ennomidse ' and ' Urapterygidae ' by M. Guenee, seems to me a 

 proof that the groups are artificial ones and should be united." 



No true CJrapterygidge have hitherto been found in the 

 United States, and very few even in the New World : those few 

 also appear to be so closely allied to some genera of Eanomidse 

 that only an arbitrary division of the two families can be main- 

 tained. On the other hand, it" we follow Dr. Packard in uniting 

 the two families, there is no knowing where to stop ; inasmuch 

 as the structure of the Urapterygidse is repeated with slight 

 modifications throughout the tribe; Thus, in the Palyadse, 

 Byssodes appropriata chiefly differs from the typical Chcerodes of 

 Guenee in the imperfect closing of its wing-cells, though its 

 style of ornamentation widely differs. The angular-winged sub- 

 caudate Microniidae, on the contrary, although eztremely like 

 Urapteryx both in form and coloration, are absolutely dissimilar 

 in the arrangement of their wing- veins, so that they ought not to be 

 associated. 



In the generic division of the Geometrites, although neuration 

 must be considered of the highest importance, it is nevertheless 

 impossible to ignore the characters off'ered by the diff'erent 

 forms of the wings, each accurately repeated in series of allied 

 species. 



In Guenee's description of Urapteryoo (translated by Walker) 

 no attention is paid to neuration; but Guenee, although he 

 evidently regarded structure as correlated with pattern and 

 coloration, did nevertheless give one plate, chiefly of neuration, 

 as illustrative of the tribe. Walker, however, ought to have 

 made some attempt to describe the wing-structure, as he not 

 unfrequently did in the case of new genera. 



I regard the method of dt scription adopted on the Continent 

 as extremely undesirable, viz. where to save the trouble of 



