256 S. W. WILLISTON, M. D. 



spines, which have a distinctly more upward curvature. The an- 

 tennae are not as Macquart figures them, but quite as Roeder de- 

 scribes them, and quite alike in both species. Gerstaecker's speci- 

 mens seem to be of a different species. 



30. Stratioinyia nititabilis Fabricius, Eut. Syst. iv, 266; Syst. Antl. 81; 



Wiedemauii, Auss. Ins. ii, 63, pi. iv, fig. 6; Perty, Delectus, etc., 184, pi. 

 xsxvi, flg. 14; Walker, List etc., v, 42, 61; Gerstaecker, Linn. Ent xi, 

 321 ; Bellardi, Saggio, etc., i, 30 ; Schiner, Novara Exped. 61 ; Osten Sacken, 

 Biol. Centr.-Amer. 37. — Mexico, Central America, Brazil. 



Stratiomys fasciata Fabricius, Eut. Syst. iv, 266; Syst. Autl. 81 (male). 



Acrochxta Aleios Walker, List, etc., iii, 526; v, 41 (Stratiomys). 



Stratiomys subalba Walker, List, etc., v, 41, 43. 



f Stratiomys subalba (Walker) Bellardi, Saggio, etc., i, 31 ; Osten Sacken, Biol. 

 Ceutr.-Amer. 37. 



Three female and one male specimen from Corumba, collected in 

 May, and as many of each sex from Chapada. The females from 

 Corumba all agree in having a narrow stripe on the hind margin of 

 the third segment and an equal band, somewhat differing in width 

 on the fourth. In those from Chapada that on the third is wanting, 

 or feebly indicated near the sides, and the one on the fourth is broader. 

 In the male from Cbrumba the wings are marked as in all the females 

 and the scutellum is margined with yellow. The male from Chapada, 

 however, has the general color deeper black, the scutellum is wholly 

 black, and the wings are almost uniforndy dark brown in front, dis- 

 tinctly darker than in the others. This male I certainly believe is 

 of the same species, and I feel equally confident that it is Walker's 

 subalba. If I understand Osten Sacken 's remarks aright, the male 

 specimen that he refers to inutabills has the abdomen marked as in 

 the females ; in my males the two yellow bauds of the abdomen are 

 extremely slender, and narrowly interrupted in the middle. 



31. 0«Ioiitoiiiyia sp. 



There are two specimens of a species of Odontomyia ( % and 9 ) 

 which I have not succeeded in identifying with any described species. 

 They are yellow, with the abdomen marked with a slender black 

 stripe, the female mesonotum with three black stripes, the middle 

 one suddenly narrowed behind the sutui'e ; in the male the whole 

 dorsum is black, with the lateral margins yellow. This is another 

 genus where he who describes isolated specimens without comparisons 

 with allied species, and the study of considerable local material, is 

 doing a positive injury. 



