24 PROCEEDINGS OF THE NATIONAL MUSEUM vol.69 



EUSIMULIUM ALTICOLUM, new species 



Female. — Entirely reddish brown; antennae large, noticeably 

 larger than fore basitarsus; front narrow; fore tarsi slender; hind 

 basitarsus with a prominent projection, the following joint without 

 dorsal incision ; claws with large basal tooth ; pilosity of wing veins 

 entirely reddish brown, abdominal tergites but little reduced. 



Length 3 mm. ; wing 3.25 mm. 



Ovipositor valves short and weak; a chitinous arm before them. 

 Cerci conical quadrate, darker than other parts; 9th sternite tri- 

 angulate, unmodified ; arm of genital rod three- fourths surrounding 

 opening, roundedly^ angled, with quadrate terminal plates and no 

 tooth. (Fig. 47.) 



Type locality. — Sierra Madre, Mexico. 



^2/^6.— Female, Cat. No. 28339, U.S.N.M. 



Distfibution. — ^Mexico: Headwaters of Rio Piedras Verdes, alti- 

 tude 7,300 feet, Sierra Madre, Chihuahua, May 9 (or September 5?) 

 (C.H. T. Townsend). 



Genus SIMULIUM Latreille 



Melusina MEaoEN. Nouvelle Classiflcatiou, 1800 (nomen nudum). 

 SimuUum Latreille, Hist. Nat. Ins. et Crust., vol. 3, 1802, p. 426. 

 Atractocera Meigen, Klass., vol. 1, 1804, p. 94. 



Perhaps most of the generic names proposed by Enderlein under 

 the subfamily Simuliinae are synonyms of the genus Siniulium as it 

 is here understood. 



Genotype. — {Cidex colombaschensis Fabricius)=6'w/'ea? reptans 

 Linnaeus. 



Description of the genus: The radius is bare along the section 

 between the stem vein and the forking of the radius; the radial 

 sector is simple ; the hind basitarsus has an apical projection and the 

 second hind tarsus has a dorsal incision. The front is usually broad ; 

 the fore tibia with or without a white poUinose patch; the fore 

 tarsi are slender or broadened; the dorsal plates of the abdomen 

 are usually much reduced and the claws may be toothed or simple. 



KEY TO THH SPECIES OF SIMULIUM, BASED ON MALE HYPOPTGIA 



AdminicuUmi broad, membranous. 



Adminiculum divided pictipas Hagen. 



Adminiculum entire. 



Clasper angled, with pilose projection at angle hydationis, new species. 



riasper not angled. 

 Clasper broad at tip with 3 or 4 teeth. 



Adminiculum arms with slight dentation vittatum Zetterstedt. 



These arms with strong dentation decwum Walker. 



