AMERICAN DIPTERA. 167 



yellowish except at tip, the remaining segments darker, the distal 

 three nearly black. Claws stout, black; the empodia about one-half 

 their length. Wings subhyaline, a little darker along the basal half 

 of the costa; veins dark brown, the anterior intercalary not forming 

 a distinct angle with that portion of the posterior cross-vein which 

 closes behind the second posterior cell; the second submarginal cell 

 not very long, the second posterior quite long, the fourth posterior 

 with a short peduncle. 



Type. — M. C. Z. A single female specimen. 



Habitat. — Nebraska (type); Springview Bridge, Brown Co., 

 Nebr. (June 10, 1902); Chicago, 111.; Columbia, O. 



Easily separated from othes Leptogasters by the striking 

 contrast between dorsum and pleurae of thorax. The above 

 description was made from the type and specimens at the 

 American Museum. 



Leptogaster obscuripennis. 



Le ptogaster obscuripennis Johnson, Proc. Acad. Nat. Sci., 1895, 

 304, 323. 

 cf $ . — Length 13-14 mm. — Head brown, face, front inferior orbits 

 and occiput covered with a dense grayish pubescence; proboscis black, 

 yellow at base; antennae yellow, the third segment and style black, 

 the former very small, suboval, much shorter than the long style. 

 Thorax brown, dorsum polished; lateral margins, pleurae, posterior 

 angles, and scutellum covered with a grayish pubescence. Abdomen: 

 first segment blackish with a prominent row of bristles on the posterior 

 margin, the second and third segments brown, the remaining segments 

 blackish with more or less brown at the anterior and posterior margins, 

 and covered with a grayish pubescence. Venter brownish. Legs red- 

 dish, thickly covered with minute yellow hairs, and dark brown spine- 

 like bristles on the tarsi; claws black, bristles on the tibiae yellow; 

 wings of a uniform dark brown; veins black. 



Type. — Collection of Prof. C. W. Johnson, Curator of the 

 Boston Society of Natural History. One male and one female 

 specimen. 



Habitat. — St. Augustine and Orlando (May 18), Fla. 



The above is Prof. Johnson's description. At the American 

 Museum there is a single specimen, 10 mm. long, from Gotha, 

 Florida, collected in March by Dr. W. M. Wheeler, which very 

 closely resembles the type, but the greased dorsum shows 

 three black stripes, the second and third abdominal segments 

 are yellowish below, blackish above, and the rest of the 



TRANS. AM. ENT. SOC. XXXV. MAY, 1909. 



