THE DIPTEROUS GENUS DOLICHOPUS IN NORTH AMERICA. 39 



213. Wings narrowed toward the root; anal angle prominent; hind margin of wing 



with a slight sinus between the anal angle and the tip of the sixth vein. 



No. 213, longipennis Loew. 

 Hind margin of wing evenly rounded; wing not narrower at root. 



No. 214, sarotes Loew. 



214. Dorsum of thorax with yello-nish gray pollen No. 203, sexarticulatus Loew. 



Dorsum of thorax with only a little grayish white pollen. 



No. 205, terminalis Loew. 



215. Hind tarsi black from the tip of the first joint, sometimes the first joint largely 



blackish 216. 



Hind tarsi yellow, at most a little infuscated from the tip of the first joint, but 

 scarcely black even at tip 217. 



216. Posterior femora with a row of bristles which end on the usual large preapical 



bristle No. 181, latipes Loew. 



Posterior femora with only one preapical bristle No. 174, aurifacies Aldrich. 



217. Humeri yellow No. 200, funditor Loew^ 



No. 201, distinctus, new variety. 

 Humeri metallic 218. 



218. About three of the upper orbital ciUa black No. 203, willistonii Aldrich. 



About six of the upper orbital cilia black No. 205, terminalis Loew. 



219. Wings a little narrowed toward the base, still the anal angle quite prominent; 



hind margin of wing with a slight sinus between the anal angle and the tip 



of the sixth vein No. 213, longipennis Loew. 



Wings not narrowed at root, evenly rounded behind 220. 



220. I have found no characters to separate the following species: No. 177, vittatus 



Loew; No. 215, cupriniis Loew; No. 216, absonus, new species; probably the 

 female of sarotes Loew (No. 214) may sometimes have a stump at the bend in 

 the last section of fourth vein, in which case it would also come in here. 



No. 1. DOLICHOPUS CALAINUS Melander and Braes. 



Dolichopus calainus Melander and Brues, Biological Bull., vol. 1, 1900, p. 138. 



Male. — Length, 5 mm.; of wing, 4 mm. Face narrow, silvery 

 white, tinged a little with yellow above. Front blue-green, shining. 

 Antennae wholly black; third joint somewhat orbicular in outline, 

 scarcely pointed at tip. Lower orbital cilia whitish. 



Thorax and scutellum dark blue, shining; pleurae green with white 

 pollen. Abdomen shining green with black incisures, slight blue re- 

 flections and spots of white pollen on its sides, Hypopygium black 

 with green reflections on basal portion; its lamellae (fig. 1) of mod- 

 erate size, somewhat triangular or almost crescent shaped, broadly 

 rounded on outer edge, brownish with black border at apex, jagged 

 and bristly below at apex, otherwise the apical border is fringed 

 with black hairs. 



Coxae, legs and feet black; anterior coxae with white pollen on 

 the front side and little black hairs. Middle and hind femora each 

 with one preapical bristle, the latter ciliated on lower inner edge 

 with black hairs, the longest of which are about as long as the width 

 of the femora; knees scarcely yellow. Tarsi wholly black; anterior 

 pair plain, but little if any longer than their tibiae, fourth joint short- 

 est, third and fifth joints of somewhat equal length; middle basitarsus 



