32 AMERICAN BLACK FLIES OR BUFFALO GNATS. 



marks, apical segrments subshining. Legs yellow, browned as fol- 

 lows: Mid and hind coxa?; fore tarsi except base; apices of first and 

 second and entire apical three joints of mid and hind tarsi; and 

 apices of hind femora and tibiaj. Wings clear, thick veins yellow, 

 costal vein darker. Halteres yellow. 



Frons divergent-sided, at least one-half as broad above antenna? as 

 at upper angle of ej^es, surface hairs yellow ; face subquadrate, nearly 

 as wide as frons at vertex; surface hairs pale, longer toward mouth 

 edge; antennal pilosity pale; postocular cilia j^ellow. Pilosity on 

 scutum short, regular, golden yellow, longer just in front of scu- 

 tellum, no black hairs on disk; pleural tuft pale; postspiracular area 

 pale-haired posteriorly ; scutellum with pilosity and upright hairs all 

 yellow. Basal fringe of abdomen pale, apical four segments with 

 rather distinct pale hairs. Legs haired as in ochraceum. Claws 

 simple. 



Length, 1-1.5 mm. 



Type. — Cat. No. 15415, U. S. National Museum. 



Locality of type. East Las Vegas, N. Mex., June 1, 1901 (T. D. A. 

 Cockerell). There are also in the national collection two females 

 from Las Yegas Hot Springs, N. Mex., August 19, 1901 (H. S. 

 Barber), and five females from Virginia Dale, Colo., September 31, 

 1912, taken on cow (Bishopp). 



Simulium notatum Adams. 



Female. — Ocherous yellow, opaque. Frons and face thickly white- 

 dusted; antennoe slightly darkened from fourth joint to apex; palpi 

 ochreous. Scutum unstriped, only two small triangular spots on 

 anterior margin and very faint indications posteriorly of the stripes 

 of the other species, laterally a darker elongated mark on disk ; pre- 

 scutum and margins of scutum adjacent to it j^ellow ; pleura? dark- 

 ened centrally, more distinctly near to coxa^; scutellum yellow; post- 

 scutum black-brown. Abdomen yellow ; segments, except apical three, 

 with opaque, black dorsal spot, apical three segments slightly shin- 

 ing, their bases browned. Legs yellow, browned, or blackened, as 

 follows: Fore tarsi, except base of first joint; last two joints of mid 

 tarsi; extreme apices of hind tibiae; and apices of basal three and 

 whole of apical two joints of hind tarsi. Wings as in hivittatum^ but 

 the costal vein paler. Halteres yellow. 



Frons divergent-sided, two-thirds as wide at above antenna? as at 

 upper angle of eyes, surface hairs weak, sparse, whitish ; face sub- 

 quadrate, surface hairs as on frons; antennal pilosity pale; hairs on 

 palpi pale; postocular cilia pale. Scutum with very pale yellow, 

 hair-like pilosity, which is distinctly longer just in front of scutellum ; 

 pleural tuft pale; scutellum with yellow pilosity and upright hairs. 



