Dec, 1804.] Tabanidae. 241 



Ball, and near Lander, Wyoming, by R. C. Moodie of Lawrence, 

 Kansas. Some slight color variations occur, and in many speci- 

 mens the antenna? are entirely black. The long stump is present 

 on the anterior l)ranch of the third vein in all the females. 



Tabanus osburni n. sp. Female: Length 12 to 16 millimeters. 

 General color of the body shining black. Eyes pilose, first and 

 second segments of the antennae black or they may be partly red- 

 dish, clothed with black hairs, third segment black except the 

 base which is red, basal portion with a blunt prominence above, 

 longer than the annulate portion. Subcallus denuded and shin- 

 ing black, frontal callosity shining black with unconnected mark 

 above; ocellar area partly denuded black, remainder of front cov- 

 ered with gray pollen; face and cheeks clothed with grav pollen 

 and dark yellowish hairs, palpi yellowish with short black hairs; 

 thorax with inconspicuous narrow gray stripes above; pleurse 

 clothed with long gray pile. Legs black but bases of tibiae show- 

 ing a reddish tinge. Wings hyaline but with costal margin and 

 narrow margins of cross-veins and furcation of third vein fuscous ; 

 these infuscations on the margins of the veins are less conspicuous 

 in some specimens than in others. Abdomen black with three 

 rows of faint gray spots above and the posterior margin of each 

 segment both above and beneath with a fringe of rather long 

 white hairs. 



Male: Length 12 millimeters. Like the fe:nale except the 

 grayish spots on the dorstim of the abdomen a]3pear to be lacking, 

 and the third segment of the antenna is noticeably narrower than 

 in that sex. This latter character is characteristic of this sex in 

 a large number of species. The head is larger and nearer 

 hemispherical than in the female. 



A large number of specimens, most of them taken bv Prof. 

 R. C. Osburn, for whom the species is named. Known from 

 British Columbia, Alberta, Montana, Washington and Alaska. 



This species is some like rhombicus but more robust and no 

 suggestion of red on the al)domen of either sex. 



Tabanus phaenops Osten Sacken. The antennae are black, 

 the wings are hyaline and the abdomen is broadlv red on the side. 

 Length 13 to 14 millimeters. Distributed from Alaska and Brit- 

 ish Columbia to California, and specimens are also at hand from 

 Wyoming and Colorado. Osten Sacken fully described this spe- 

 cies in his paper on ' 'Western Diptera" and his description should 

 be consulted. 



Tabanus procyon Osten Sacken. The palpi, legs and anten- 

 nae, as well as the whole body, are black; the subcallus is denuded 

 and shining black, the wings are hyaline except the costal cell, 

 margins of cross-veins and furcation of third vein which are black. 

 Length 1.3 millimeters. Known from California, and specimens 

 are at hand from Eldorado collected bv Sarah E. Harris. 



