36 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 69 



liind femora but slightly thickened, spinose on posterior two-thirds 

 of ventral surface; discal cross vein of moderate length, but little 

 oblique. 



Walker's description of this species states that the abdomen is 

 linear, a little narrower than the thorax and " fully thrice its length." 

 In Williston's quotation, it is stated " fully twice its length." How- 

 ever, the abdomen is not unusually long. In form and size it is an 

 average species of Xylota. The unusual length of the abdomen, as 

 given by Walker, led Williston to believe that it might be the same 

 as his species elongata = (female angustiventrls) . 



Metcalf has figured the genitalia of f,avifrons under the name 

 Xylota ohscura Loew. 



Distribution. — Walker's material of -fiavifrons and communis came 

 from St. Martins Falls, Canada. X. ohscura Loew was recorded 

 from the Red River of the North, Canada. The species has been re- 

 corded under the name ohscura from Washington, Oregon, and Cali- 

 fornia (Williston; but all three of these vQ.coYds=:harhata Loew); 

 Nebraska (Hunter) ; Wisconsin (Graenicher) ; Connecticut (Brit- 

 ton) ; Oregon (Lovett and Cole); Colorado (Jones). Material at 

 hand: Franconia, New Hampshire (Mrs. A. T. Slosson), North 

 Mountain, June 8, 1898 (C. W. Johnson), Lake Tear, Mount Marcy, 

 4,300 feet, July 12, 1918 (W. T. M. Forbes). 



Type. — In British Museum. 



XYLOTA BARBATA Loew 



Rather large, robust species, 10-13 mm. Antennae black, third 

 joint rounded, arista black. Longer than width of face; fore basi- 

 tarsus of male without long hair, ventral surface with 4-5 spines 

 basally and 2-3 apically; metasternum pubescent; hind trochanters 

 of male with short spur; second and third tergites opaque black, 

 each with a pair of large bluish-black metallic spots; discal cross 

 vein joining discal cell beyond middle; posterior cross vein longer 

 than section of fourth vein above it ; metathoracic spiracle unusually 

 large, larger than third antennal joint. 



Distribution. — -Apparently a common species west of the Rocky 

 ^Mountains. Has been taken at Kaslo, British Columbia, and is re- 

 ported from Quebec (Gibson). 



Type. — In Museum of Comparative Zoology. 



XYLOTA ANGUSTIVENTRIS Loew 

 Xylota clongaia Williston, in pari. 



A fairly large, elongate species, 9-13 mm. 



Antennae and arista black, third joint large, longer than broad and 

 longer than front in female, measured across ocelli ; arista longer 

 than width of face; pale parts of legs very light yellow; fore basitar- 

 .sus of male without long hair, ventral spines present; metasternum 



