312 DIPTERA FROM SOUTHWESTERN UNITED STATES 



Prcsiitural acrostichals irregularly four-rowed, weak, of moderate length, 

 the outer two rows longest; prealar nearly as long as the bristle behind it. 

 Abdomen about twice as long as wide, parallel -sided; fifth sternite with 

 \\caker but more numerous discal bristles than in marginata, the inner margin 

 of each process with minute spinules which are verj' noticeably shorter than 

 those of })iarginata (figs. 5 and 8) ; hypopigium differing from that of marginata 

 in having the dorsal processes stout and blunt at apex (figs 10 and 11). Chae- 

 totaxy of legs as in marginala but the bristles are longer and stronger. 



Fonalc. — DifTers in color from the male in having the body less shining and 

 not so deep black, owing to the presence of brownish yellow pruinescence. 

 The head is entirely black, with the interfrontalia opaque, almost velvetj- 

 black. The thorax and abdomen are less distinctly vittate than in tlu> male, 

 and the wings are paler at base. 



Stnicturally and in chaetotaxj' the species closel}' resembles spiniventns 

 Coquillett and marginata Stein but the arista is much shorter haired than in 

 either of these species. Length, 6.75 mm. 



Type. — cf ; Tennessee Pass, Colorado, July 24, 1917, (Aldrich), 

 [Coll. Illinois]. Paratypes. — 4 cf, 6 9, Beulah, New Mexico, 

 June 28, 1902, top of range. 



A female from Redwood Caiion, ]\Iarin County, California, 

 May 17. 1908, may be this species. 

 Hylemyia spinilamellata sp. n. 



Male. — Similar to the last species in color. 



Stnicturally similar to the preceding species, but differing from it in that 

 the longest hairs on the arista are as long as the width of the tliird antennal 

 joint, the eyes are a Uttle closer together, the presutural acrostichals cover a 

 narrower strip, the processes of fifth abdominal sternite are armed with longer 

 stout spines on basal half of inner margin (fig. 7), and the hypopygium is en- 

 tirely different (fig. 9). 



Female. — Similar to the female of the preceding species, but having the arista 

 with much longer hairs. Length, 6 to 7 mm. 



Type.— &; Silver Lake, Utah, July 10, [Coll. Illinois]. Para- 

 types. — 2 9 , Beulah, New Mexico, June 28, 1902, top of range. 



This species is more closely allied to marginata Stein than to 

 marginella, but the Jiypopj'gium is entirely different from that of 

 marginata as shown in figures. The male has xevy short, regular 

 bristles on antero- ventral surface of n id femora, which become 

 shorter towards apex, whereas in the other species the bristles 

 are very long and generally confined to basal half. The costal 

 thorn is absent in t3^pe. 



