248 PROCEEDINGS OF THE NATIONAL MUSEUM vol. no 



Because the majority of the material seen was from Canada, the 

 United States, and Mexico, the treatment of the species occurring in 

 these regions is more complete than that for Central America and 

 South America. In many cases only one or a few determined speci- 

 mens of a species from the latter regions were seen. No doubt more 

 described species of South American Apion wUl be found to belong to 

 this subgenus when determined material is available for study. 



Tnchapion Wagner (1912) was proposed as a subgenus for 16 new 

 species described from Mexico and Central America. No tj^pe species 

 was designated. I hereby designate Apion {Tnchapion) aurichalceum 

 Wagner as the type species of subgenus Trichapion Wagner. This 

 species is selected because it is relatively abundant. In addition I 

 was able to study a pair of specimens determined by Wagner and 

 I am informed hy Mr. J. Balfour-Browne that the types of this species 

 are in good order. 



No previously described species were included by Wagner in the 

 subgenus. With the exception of Voss (1955), whose paper is dis- 

 cussed below, the name Trichapion has not been used in the literature 

 since it was first proposed. At the present time 92 of the approxi- 

 mately 425 New World species of Apion are kno\vn to belong to this 

 subgenus. Fall (1898) divided the North American Apion into four 

 groups. His group No. 3 corresponds quite closely to subgenus 

 Trichapion Wagner. 



Voss (1955) uses Trichapion Wagner as a subgenus for 18 species 

 of Apion from Ruanda-Urundi, Belgian Congo. Because Voss does 

 not mention the chief diagnostic character of the subgenus — the mu- 

 cronate tibiae of the males— in the descriptions of the species he m- 

 cluded in subgenus Trichapion, it may be that the African species are 

 incorrectly assigned. 



At the present time it is difficult to define a subgenus of Apion. 

 The chief reason is the large number of species not assigned to sub- 

 genera. In the New World six subgenera have been erected, viz., 

 Bothryopteron Wagner with four species, C'oelocephalajnon Wagner 

 with sLx species, Coleopter apion Wagner with five species, Heterapion 

 Sharp with two species, Stenapion Wagner with 18 species, and Tricha- 

 pion Wagner with 92 species. In this region 127 out of about 425 

 species of Apion have been placed in subgenera. Previous to the 

 present study no species of Apion from the United States were placed 

 in a subgenus. The majority of Apion subgeneric names have been 

 founded on European species, that is, 30 out of 42 subgenera founded 

 on approximately 250 species of Apion from Europe. From a world- 

 wide standpomt well over a thousand species of Apion have not been 

 assigned to subgenera. 



