ART 11. NOTES ON" NEARCTIC BIBIONID FLIES — McATEE. 25 



FcTYiale. — Similar to T). hreviceys in coloration, but distinguished 

 from this and other species by the conspicuous development of the 

 prothoracic comb; head black; rostrum of ordinary length; thorax 

 rufous, touched with black on pleura, and combs, the anterior of 

 which is very strongly developed, with long stout teeth, height of 

 comb nearly equal to length of eye ; abdomen brown, darker basally ; 

 coxae and femora chiefly rufous, trochanters, ends of femora, tibiae 

 and tarsi black; hairs pale except on tarsi and to some extent on 

 tibiae; halteres with dark knob and pale stalk; wings yellowish to 

 dusky f umose, veins near costa and large stigma dark brown. Length 

 of wing, 6 mm. or slightly less. 



Type, a female from Catalina Island, California, Baker (U.S. 

 N.M.). Paratypes include a female, with same data, and numerous 

 specimens of both sexes from Mount Lowe, July 3, 1917, and Mount 

 Wilson, California (Aldrich). A female from Palo Alto, California. 

 May 1, 1906, also is included here, but is not made a paratype; it is 

 somewhat intermediate in characters between strigilatus and occipi- 

 talis. 



Type.— Cut No. 24705, U.S.N.M. 



DILOPHUS TIBIALIS Loew. 



Dilophus tibialis Loew (H.), Dipt. Amer. sept, indlg., Cent. 9, No. 61, 1869; 

 Compl. Work, vol. 2, p. 200 [Sitka]. 



MaJe. — Head, body, and legs brownish to black, chiefly shining, 

 with copious, rather long pale hair ; genital segment cleft only about 

 one-fourth its length, superior plate almost straight across hind 

 margin ; wings and veins nearly hyaline, membrane somewhat fumose 

 costally, veins brown; stigma nearly obsolete, the vein running 

 through it distinct. 



Female. — Head, body and legs with copious, rather long pale hair, 

 as in male ; head, top of thorax chiefly, pleura in part, and scutellum 

 brownish black or black, shining; abdomen pale brown to brownish 

 black; humeri, pleura in part, coxae (at least the front ones) and 

 femora yellow to rufous ; mid and hind coxae sometimes, trochanters, 

 tibiae and tarsi brownish to black; wings as in male, the stigma a 

 little more distinct. 



Length of wing, 5-6.5 mm. 



Specimens examined are from Berg Bay, Yakutat, Sitka, and 

 Juneau, Alaska. 



SPECIES NOT IDENTIFIED. 

 DILOPHUS FULVICOXA Walker. 



Dilophus fulvicoxa Walkeb (Francis), List Dipt. British Mus., pt. 1, 1848, 

 p. 117 [St. Martin Falls, Albany River, Hudson Bay]. 



DILOPHUS LONGICEPS Loew. 



Dilophus longiceps Loew (II.), Dipt. Amer. Sept. indig., Cent. 1, No. 14, 

 1861, Corapl. Work, p. 9 [Illinois]. 



