346 ERNEST A. BACK 



punctate appearance. The bristles before the transverse suture of 

 the thoracic dorsum much shorter than in the other species, upon the 

 posterior callosities are very much reduced, and upon the posterior 

 margin of the scutellum there are about six reduced to mere denticles; 

 the remainder of the scutellum above bears the same short bristly hair 

 as the thoracic dorsum. Halteres yellowish. Abdomen rather short 

 and stout. Legs black. Mystax and short bristles and hair of entire 

 body and legs black. Wings brown or black; veins black, the fourth 

 posterior cell narrowly open. 



9 ■ — Like the male in body structure and presence of bristly pustules, 

 but as in combustus and dispar, the female is more reddish. Head, 

 black; mystax and pubescence of face yellow; antennae reddish, be- 

 coming dark brown toward the tip; proboscis black, slightly brownish 

 at the base. Thorax black as in the male, but the lateral margins of 

 the scutellum and the metanotum are brownish and the bloom is 

 yellowish, not silvery- white. The first and seventh segments of ab- 

 domen black, the others red, with the lateral margins black; the pos- 

 terior margin of the second segment is narrowly black, on the other 

 seginents the black of the lateral margins extends upward but slightly 

 on the posterior margin. Halteres and legs reddish; coxae, tips of 

 hind femora and the bases of the tibiae, with a very narrow black ring, 

 the last segment of the front and middle tarsi also black; spines of 

 tibiae few in number, mostly white, those on the tarsi numerous and 

 black. Wings light brownish, the veins on the basal half bright yel- 

 low; the fourth posterior cell closed and slightly petiolate or narrowly 

 open. 



Type. — The unique type of both bicolor and abbreviatus are 

 in the collection of Prof. C. W. Johnson, Curator of the Boston 

 Society of Natural History. 



Habitat. — Near San Antonio (type), and Cotulla (J. C. 

 Crawford, May 5, 1905), Texas. Mr. Crawford captured his 

 specimen on Coreopsis cardamine folia. 



Because of the denticles of the scutellum, the bristly pustules 

 and the rather "chunky" build, this species seems rather out 

 of place with the other forms now included in this genus from 

 the United States. Prof. Johnson hesitated in placing it in 

 this genus and did so only after showing specimens to Mr. 

 Coquillett, who at that time thought that the species did not 

 possess sufficient characters to warrant its separation from 

 Sarapogon. Mr. Coquillett, however, now is inclined to be- 

 lieve that it should be placed in a new genus. I agreed with 

 him at first, but recently have seen, through the kindness of 



