AMERICAN DIPTERA. 15 



above black. Tliorax in profile remarkably convex and high, the convexity be- 

 ing greater on the front part, bare except with four rows of moderately strong 

 bristles; of a rich brown color, with an irregular white stripe on the side in front. 

 Pleurae dark brown, lightly poUinose. Scutellum small, bare except two erect, 

 black bristles at the tip ; metanotum thickly white pollinose. Abdomen gently 

 convex, and gently and evenly tapering from the base to the tip, brownish black, 

 shining, with distinct gray pollinose markings, as follows: on the anterior margin 

 of the second segment with an interrupted narrow cross-band, and a little beyond 

 it two narrow transverse spots forming an abbreviated interrupted cross-band, 

 near the middle and touching the lateral margin another smaller spot; third, 

 fourth, fifth and sixth segments with an interrupted abbreviated cross-band, and a 

 smaller lateral spot near the middle. Legs black, femora with sparse white pile, 

 tibiae with white bristles, the posterior tibiae considerably thickened gradually 

 from the base, the metatarsi also Somewhat thickened. Wings hyaline, all the 

 cross-veins and base of first submarginal cell, and the costa from the tip of second 

 to the tip of fourth vein narrowly clouded with dark brown, a similar cloud at the 

 furcation of the third vein, the anterior branch of which is angulated and with a 

 minute stump of a vein. 



One specimen, California (Baron). 



This species does not belong in Cyrtopogon. but may be provisionally 

 placed here till a better place is found for it. It shows some relationship 

 to Holopogon, but not as much as to several of the species from the West 

 now placed under Cyrtopogon. The structure appears to be the same 

 as the species described by Bigot as Holopogon? append icidaf us 

 but it cannot be the same species, as will be seen by comparison of the 

 description of the thorax, abdomen, legs and wings. Cyrtopogon cerux- 

 satits 0. S., must also somewhat resemble this. The convexity of the 

 thorax, which is " Kaputzenartig " resembles very much that of Pseiidoriis 

 hicolor Bell as figured by Bellardi, and is seen in a less degree in our 

 species of nolcoaphtda. 1'he face in profile is gently convex from 

 the antennae to the oral margin, but is most projecting below. The 

 species is very thinly pilose. 



PYCMOPOGON. 



i'4. Fyciiopo^oii cirrliatus Osten Sacken, West. Dipt. 293. 



A single male specimen from Northern California. The dorsum of the 

 thorax is short black pilose across the middle. This species seems to be 

 rightly placed, but the difference between this genus and Anisopogon 

 must be slight. The short abdomen and the thick pilosity on its dorsum 

 will hardly allow the species to be placed under Anisopogon., but these 

 are the sole diff"erences. 



ANISOPOGON. 



'lb. Aiiisopogoii senilis Bigot, Annales Soc. Ent. Fr., 1878, 42.'?. 



A female with the preceding species, from which it differs chiefly in 

 the abdomen being nearly bare above, clothed only with short black pile. 



