ALDRICH AND DARLINGTON. 81 



Iberia def'essa Osten Sacken. 



Length 5.5 mm. ; of wing 6.2 mm. 



Head yellowish ; occiput brownish pollinose ; front pale yellow, wholly pubes- 

 cent; foremost fronto-orbital bristle about half the size of the posterior one; 

 antennae reddish-brown, third joint roundish, rather large; arista only micro- 

 scopically pubescent; face receding; cheeks one-half the width of the eye; 

 vibrissse one on each side, rather strong. 



Dorsum of thorax grayish-brown ; the dorso-central bristles arise from large 

 brown spots and the small hairs from smaller spots; a middle brown line runs 

 almost the whole length of the thorax; humeri yellow; pleura rather dirty 

 yellow; mesopleura rather sparsely pubescent; sternopleura, besides the one 

 strong bristle, densely pubescent all over; scutellum bare except the ordinary 

 four bristles, yellow. 



Abdomen gray; haltei'es yellow; hypopygium of the male of medium size, 

 yellow. 



Wings with a brownish yellow tinge. 



Legs yellow ; front femora somewhat infuscated. 



Four males and nine feniale.s. Melander: Indiana. U. S. N. 

 M. : Cheat Mt. Cave, Files Creek, AVest Virginia; Boone's Cave, 

 Hickman's Landing, Kentucky. Johnson : Niagara Falls, New 

 York, June 28th. 



This species was first described from a cave in Kentucky, and 

 has been reported from other caves in Kentucky and Indiana. See 

 note by Blatchley under (Ecothea fenestralis. 



Liei'ia biweta Loew. 



Length 5.7 mm. ; of wing, 6.4 mm. 



Yellow, abdomen somewhat infuscated ; in general appearance resembles the 

 genus Helomyza. 



Head yellow, front lemon-yellow, lower part pubescent; antennse reddish- 

 yellow, third joint round, arista rather long, only microscopically pubescent; 

 cheeks straw yellow, about three-fourths the width of the eyes, which are round, 

 occiput entirely yellow, a tuft of small black hairs parted in the middle at the 

 base of the occiput. 



Thorax yellow, the dorso-pleural suture reddish, dorsum rather densely pubes- 

 cent; scutellum lemon-yellow, bare except the ordinary four bristles; mesopleura 

 bare except a few very small hairs on the anterior edge; sternopleura with two 

 strong bristles of nearly equal size on the upper edge, also with sparse pubescence. 



Abdomen blackish-yellow; the second, third and fourth segments with a black 

 posterior margin ; hypopygium of the male bright yellow, rather large and 

 densely pubescent. 



Wings large, with a brownish-yellow tinge; the hind cross-vein and the apices 

 of the longitudinal veins distinctly bordered with brown ; spines of the costa 

 yellow. 



Legs yellow, densely covered with black hairs; distal end of the hind femur 

 black ; the last four tarsal joints of the front legs black; pulvilli white, rather 

 conspicuous. 



TEANS. AM. ENT. SOC. XXXIV. (11) MAKCH, 1908. 



