AMERICAN DIPTERA. 



Pliora pacliyneiira Loew. (Figs. 1 and 2.) 



341 



Loew, Centuries, vii, 97 (1866). 

 Female. Length 2.6-4.2 mm., of wing 3-4 mm. Moderately stout, black, the 

 abdomen opaque, thorax and front subopaque, face shining. Head small, black ; 

 antennae, and palpi of the same color; proboscis exserted, very stout and horny ; 

 front broad, short, rather convex, the setae all turned upward. Scutellum with 

 four marginal bristles. Feet piceous black, knees yellow, hind femora rather 

 broad; middle tibiae above near the base with two small setse, front tibiae with 

 one very minute one, and hind tibite unarmed. Halteres black. Wings cinere- 

 ous, the costa with very short cilia ; heavy veins brownish black, the third very 

 stout, furcate ; the light veins brownish, toward the apex paler and thinner, the 

 first bent near its base, the fourth subobsolete and greatly abbreviated. 



The male differs in having the palpi larger, very shining and with 

 very weak bristles. The antenna? are much larger than in the 

 female and velvety black. 



Alaska; Moscow, Idaho; March 17; Wisconsin (Wheeler); 

 Olympia, Wash. (Kincaid) ; Seattle Wash. (Johnson); Montreal, 

 Que. (Johnson). 



This large and stout species can always be recognized by the 

 extremely thickened third longitudinal vein, which is thicker than 

 the costa at its center. 



Pliora fratercula sp. nov. (Fig. 3.) 

 Male. Length 2 mm. Head, thorax and abdomen black. Dorsum of thorax 

 somewhat shining, sparsely covered with fine black hairs arranged in longitudi- 

 nal rows. One pair of dorsocentral macrochaetae and two marginal scutellar bris- 

 tles. Front short, one and three-fourths times as wide as long, with the usual 

 bristles. Antennae black, of rather large size, strongly black pubescent; arista 

 pubescent and much thickened at the base. Palpi small, black, the usual lateral 

 bristles present, well developed. Abdomen dull black, grayish pollinose. 

 Hypopygium of rounded form, black and slightly pollinose. Legs long 

 and rather slender, piceous; a little lighter on the anterior coxae and at the 

 knees. Anterior tibiae with a delicate external bristle at basal third ; middle 

 legs with a pair and hind legs with a single bristle at the basal third, stronger 

 than the ones on the anterior legs. Middle tibiae with one and posterior tibiae 

 with two apical spurs. Halteres varying from light browuish to black. Wings 

 very slightly infuscated, the costal vein with short, rather closely placed bristles; 

 reaching to the middle of the wing. First vein ending midway between humeral 

 vein and tip of costa; fourth vein arising at the furcation of the third, ending 

 just before the wing tip, not recurved at the tip ; fifth vein ending much behind 

 wing tip; seventh vein wanting, so that there are only three light veins in 

 the wing. 



Described from two male specimens, collected by Dr. Win. M. 

 Wheeler, at Jackson's Lake, Wyoming, September 16, 1895. 



This pretty species is related to the European P. trinervis Beck., 



TRANS. AM. ENT. SOC. XXIX. OCTOBEE. 1903. 



