114 MOSQUITOES OF NORTH AMERICA 



Obioinai. Descbiption of Wthmmyia abia: 



Female. — Proboscis slender, moderately long, much swollen at the apex; palpi 

 dark-scaled; occiput dark-scaled, with obscure blue and green luster, the eyes nar- 

 rowly margined with dull white scales, the margin interrupted toward the vertex; 

 prothoracic lobes clothed with pearly iridescent scales, the apices without white 

 tips; mesonotum bronzy-scaled, with obscure bluish reflection; abdomen bronzy- 

 scaled above, with bluish reflection, beneath coarsely white-scaled, the colors sepa- 

 rated on the sides in a straight line; legs dark-scaled, with bronzy and blue re- 

 flections; mid-tarsi with the apical half of the second and all of the third and fourth 

 joints silvery white-scaled on one side; front and hind tarsi unmarked. Length, 

 3 mm. 



Male. — Coloration as in the female. 



Two specimens, Dominica, West Indies. (F. B. Campbell.) 



Type.— Cat. No. 11988, U. S. N. M. 

 Descbiption of Female, Mat.e, and Labva of Wteomyia abia: 



Female. — Proboscis moderate, tip somewhat expanded, labellae small, 

 rounded, with fine outstanding setae ; vestiture bluish black. Palpi short, flat- 

 tened, one-sixth as long as the proboscis, bronzy black. Antennae moderate, 

 the joints slender, subequal, rugose, coarsely pilose, black; tori subspherical, 

 with a cup-shaped apical excavation, yellowish brown, with a whitish prui- 

 nosity; hairs of whorls long, rather sparse, black. Clypeus rounded triangular, 

 convex, dark brown, pruinose. Eyes separated at vertex by a narrow wedge, 

 bluish black. Occiput clothed with flat brown scales with a bronzy and blue 

 reflection, a small metallic spot at vertex and a large white spot at lower part 

 of sides; two long setae at vertex and smaller ones along margins of eyes. 



Prothoracic lobes elliptical, well separated, clothed with flat bluish scales, 

 with bronzy luster and broad white tip ; a row of setae along anterior margin. 

 Mesonotum clothed with elliptical, flat dark-brown scales with a bronzy and 

 blue reflection; scales under lateral angles dull gray, with bluish reflection; 

 setae over roots of wings dark brown. Scutellum trilobate, with vestiture 

 similar to and continuous with that of mesonotum, each lobe with a small tuft 

 of black bristles. Postnotum elliptical, prominent, a broad, low median carina, 

 dark brown, a group of small setae near posterior margin. Pleurae dark brown, 

 coxae luteous, clothed with elliptical, flat silvery-white scales. 



Abdomen subcylindrical, compressed, truncate apically and with many long, 

 dark-brown terminal setae ; dorsal vestiture black, with a slight metallic reflec- 

 tion ; venter yellowish white, the colors separated at sides in a straight Une. 



Wings moderate, hyaline; petiole of second marginal cell less than one-half 

 as long as its cell, that of second posterior cell as long as its cell ; basal cross- 

 vein distant nearly its own length from anterior cross- vein; scales of veins 

 Ugulate, rather long, black, with a slight bronzy reflection on the costa, denser 

 and broader on second to fourth veins outwardly. Halteres whitish with black 

 knobs. 



Legs moderate, slender, black with a bronzy reflection, the femora whitish 

 beneath; tibiae and tarsi with a strong bronzy luster beneath; middle tarsi with 

 outer half of second and the third to fifth joints silvery white, except beneath. 

 Claw formula, 0.0-0.0-0.0. 



Length: Body about 3 mm.; wing 3.5 mm. 



Male. — Proboscis brighter bronzy beneath than in the female, becoming 

 silvery toward the base. Palpi slender and very short. Antenna similar to those 

 of the female, hairs of whorls longer and more abundant. Coloration as in the 

 female. Wings similar to those of the female, the basal cross- vein about its own 

 length from anterior one. Legs marked as in the female ; mid tarsi with two 

 unequal, opposed claws, those of the hind tarsi small and nearly equal ; formula, 

 0.0-0.0-0.0. 



Length : Body about 3 mm ; wing 2.5 mm. 



Genitalia : The abdomen of our single male has been lost. 



