36 Everett E. Wehr 



Chrysogaster robusta Shannon. Proc. Ent. Soc. Wash., xviii, 101 

 (1916). 



A $ collected in the Bad Lands at the mouth of Monroe 

 Canyon, Sioux County, May 28th, 1901 (L. Bruner). 



Chrysogaster nigripes Loew. Cent., iv, 60 (1863); WiUiston, Synop. 

 N. A. Syrph., 33 (1886). 



A s taken at Cedar Bluffs, Saunders County, in April. 



Chilosia Meigen 

 KEY TO THE SPECIES 



Face bare; pile on mesonotum short; everywhere profoundly punc- 

 tured pnnctulata 



(Face hairy; pile on mesonotum long; not profoundly punc- 

 tured Uvida) 



Chilosia punctulata Hunter. Canad. Ent., xxix, 128 (1897). 



This species is not represented in the University collection, 

 altho it is recorded by Hunter as having been collected at 

 West Point, Cuming County, on September 9th. 



I take this opportunity to present the description of a new 

 Chilosa from Colorado, as follows: 



Chilosia livida n. sp. 



S. Length 9-11 mm. Eyes hairy. Face and cheeks a bright blue- 

 green black, the ocular depression with a faint pinkish tinge, white pilose 

 except the oral margin and tubercle, face deeply concave just below the 

 base of the antennae where it is whitish pollinose. Front a dull blue- 

 green black, with a longitudinal depression and covered with moderately 

 long pale yellow pile. 



Dorsum of thorax bright greenish black, covered with moderately 

 long pale yellow pile; pleura colored like the dorsum of the thorax with 

 long whitish pile. Scutellum bluish black. 



Abdomen bluish black with a very faint greenish tinge, the first three 

 tergites darker than those following due to a covering of short black 

 hairs. Lateral margins of abdomen with long white pile. Venter 

 whitish pilose. 



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