,1. R. MALLOfH 157 



Typc—d"; Pdpoff Island, Alaska, July U, 1899, (Kincaid), 

 [U. S. N. M.]. 



This is the species recorded by Coquillett as Lasiops hirsutula 

 Zetterstedt, in the report on the Diptcra collected by the Harri- 

 man Alaska Expedition.^ 



From coquiUetti, hirsutula differs in having the prealar bristle 

 long; mid femur with a series of short stout spines on basal half 

 of ventral surface instead of very weak hairs; the hind tibia 

 with two or three postero-dorsal bristles, the antero-ventral hairs 

 much longer than the diameter of the tibia and the posterior 

 surface with long hairs, and the fourth joint of mid tarsus much 

 longer than broad. 



Trichopticus conformis sp. n. 



Male. — Black, slightly shining, thorax and abdomen with tlen.sc golden 

 brown pruinescence, the former with two narrow sul)mcdian, and two broad 

 sublateral black vittae, the abdomen with a narrow black dorso-central vitta, 

 which is slightly dilated at apex of each segment. Antennae and palpi black. 

 Legs yellow testaceous, the coxae, trochanters, fore femora and tarsi infus- 

 cated. Wings hyaline, yellow at bases. Calyptrae and halteres yellow. 



Eyes hairy, separated by about width of anterior ocellus; parafacials about 

 half as wide as third antennal joint and half as wide as height of cheek; an- 

 tennae elongate, extending almost to mouth-margin, third joint twice as 

 long as second; arista with longest hairs not longer than its basal diameter. 

 Thorax with two strong pairs of presutural acrostichals and four pairs of 

 postsutural dorso-ccntrals; prealar bristle more than half as long as the one 

 behind it. Abdomen broadly ovate; hypopygium as in figures 9 and 10; 

 fifth stcrnite with rather dense setulose hairs on disc, the posterior margin 

 with a broad, shallow, rounded emargination (fig. 11). Fore tibia with 

 from one to three posterior bristles; fore tarsus normal, longer than tibia; 

 mid femur normal in shape; mid tibia with one or two antero-dorsal, two 

 or three postero-dorsal and two or three postero-ventral bristles; hind femur 

 with a series of bristles from base to apex, which increase in length to near 

 apex and then decrease; the ventral surface with munerous erect short hairs; 

 hind tibia with from five to eight antero-ventral setulae, the anterior and 

 antero-dorsal surfaces with erect short hairs, among which, on the latter 

 surface, are two or three longer bristles, the postero-dorsal surface with a 

 long median bristle, and a few erect hairs on the posterior surface. Costal 

 thorn minute; outer cross-vein slightlj^ curved. 



Female. — Similar in color to male. 



Eyes separated by one-third of the head-width; interfrontalia without 

 cruciate bristles; lower, forwardly directed, supraorbital bristle much longer 

 and stronger than second. Armature of fore and mid tibia as in male; hind 



^ Proc. Wash. Acad. ScL, ii, p. 444. 



TR.\ys. AM. ENT. SOC, XLVI. 



