144 THE CANADIAN ENTOMOLOGIST 



thorax blackish with the usual faint, pale lines ; antealar tubercle black ; abdomen 

 dorsally with 1st segment almost entirely black, slight traces of orange being 

 visible on the extreme lateral posterior area; a broad (2mm.) black dorsal band 

 crosses segments TI-IV, the lateral areas being deep orange-red, remaining seg- 

 ments black ; slight traces of a paler flesh-colored oblique stripe on the red area 

 of segment II; ventrally orange-red the posterior border of the 1st segment and 

 the last three segments blackish ; legs with all femora black, anterior tibiae tinged 

 with orange proximally, other tibiae entirely dull orange; wings hyaline with 

 costal cell brownish and a faint brown cloud at the base of the anterior branch 

 ' of 3rd vein. Length 14mm. 



Holotype. 1?. Cxallatin Co., Montana (July 14th., 7500 ft) in Canadian Nat- 

 ional Collection. 

 Paratypci, 2$'s, Gallatin Co., Montana (July 27th., 5500 ft.) in Collection of 

 Montana Agr. Coll.; Cowley, Alta. (Sept., R. N. Chrystal) in 

 Canadian National Collection. 

 The species closely resembles phaenops but differs in the denuded sub- 

 callus, the redder antennae, the broader black area on 1st abdominal segment and 

 the cloud on the outer cross-vein ; none of the specimens before me shows any 

 trace of a stump at the base of the anterior branch of vein 3 as is so often seen 

 in phaenops ; the extent of the black area on the first segment may be variable 

 and should not be too much relied on as a sole means of separation from phae- 

 nops. 



Tabaniis atrobasis, sp. nov. $. Palpi orange, heavily clothed with short black 

 hair, not swollen at base ; antennae black with 2nd joint and basal portion of 3rd 

 red; dorsal angle at base of 3rd joint obtuse, with little excavation, this whole 

 portion being rather slender ; subcallus and front covered with pale yellowish 

 pollen, latter moderately (.5-. 75mm.) broad with shiny black-brown callosity ex- 

 tejided towards as usual by a fine black line ; thorax blackish with the five pale 

 lines as usual and a black antealar tubercle; abdomen with first segment dorsally 

 entirely black except a very narrow line of orange along posterior margin; second 

 to fourth segments laterally orange, shaped somewhat with brownish ; a broad 

 (2mm.), black, dorsal band with more or less distinct central row of triangular 

 pale spots situated on rear margin of segments and clothed with pale yellowish 

 hair; last three segments blackish; rear margins of all segments with yellow hair; 

 ventrally dull orange, shaded with smoky and with rear segments entirely black. 

 Legs black, anterior tibiae slightly, other tibiae almost entirely dull-orange. 



Length 16-17 mm. 

 Holotype. 1$, Mt. Lehman, B. C (May 30th., S. Hadwen) in Canadian Nat- 

 ional Collection. 

 Paratypes. Numerous $'s from various B. C localities (Mt. Lehman, Victoria, 

 Duncan, Courtenay, Royal Oak) in Canadian National Collection. 

 The species has apparently been confused with both ,<;pnomensis and 

 captonis; the entirely black first abdominal segment seems quite characteristic 

 and separates atrobasis from both the above mentioned forms; it is considerably 

 larger than sononieri.sis and lacks the denuded subcallus and chunky third anten- 

 nal joint of captonis. The species extends south into Oregon, a number of speci- 

 mens having been received from Prof. Lovett, labelled either sonomensis or 

 epistates. 



