84 AMERICAN DIPTERA. 



I^ieria discolor Loew. 



Lengtli of body 5.4 mm. ; of wino; 4.6 mm. 



General color yellow; abdomen somewhat darker. 



Head yellow; front safi'ron -yellow, wholly pubescent; antennae same color, 

 third joint round ; arista noticeably enlarged at base, the base yellow, remaindei' 

 black, only microscopically pubescent; cheeks about one-half the width of the 

 round eyes, straw yellow; vibrissse one on each side, rather large and strong; 

 orbits of the eyes somewhat silvery pollinose. 



Thorax yellow ; dorsum densely pubescent with black hairs; scutellum bright 

 yellow, bare except the ordinary four bristles; mesopleura yellow, bare except 

 three or four small hairs at the lower anterior corner; sternopleura with one 

 strong bristle and about five small hairs on the upper edge, also numerous hairs 

 on the lower part. 



Abdomen yellowish-brown ; hypopygium of the male yellow, of medium size. 



Wings unspotted, almost hyaline; wing veins yellow; spines of the costa 

 rather small. 



Legs yellow; tarsi somewhat darker; pul villi dirty white, rather conspicuous. 



One male and three females, from the type locality. U. S. N. 

 M. : Mt. Washington and White Mountains, New Hampshire. 



Iberia serrata Linn. 



Length 5.3 mm. ; of wing 5.9 mm. 



Head yellow, occiput black ; front saffron-yellow above, lighter below, densely 

 pubescent; first two joints of the antennae yellowish-brown ; third joint black, 

 arista long, only microscopically pubescent; cheeks yellow, three-fourths the 

 width of the eye; more than one vihrissae on each side. 



Thorax ash-gray, densely pubescent ; a narrow brown stripe runs down the 

 middle, with a wider one on each side, from which the dorso-central bristles 

 arise; scutellum ash-gray, bare except the ordinary four bristles; mesopleurse 

 bare except a few small hairs at the lower anterior corner; sternopleura, besides 

 the one strong bristle, with rather dense pubescence. 



Abdomen wholly reddish-yellow or saffron-yellow, hypopygium of the male of 

 the same color, small. 



Wings grayish translucent, veins yellowish-brown. 



Legs yellow; front femora infuscated on the outside; last three or four tarsal 

 joints of all the legs blackish. 



Nine males and nine females. Cooley : Bozeman, Montana, May 

 27th to July 7th. Melander: Mayfield Cave, Bloon)ingtou, Indiana. 

 Brues: Horseshoe Cave, Door County, Wisconsin, July 13th. Aid- 

 rich: Moscow, Idaho. 



The preceding species is very similar in appearance to Tephro- 

 chlamys rufiventris ; it can be distinguished by having four dorso- 

 central bristles, shorter antennae and more bristly epistoma. 



The earliest described species of the family ; common in many 

 parts of Europe as well as North America; frequently collected in 

 caves, also on windows of houses. According to Brauer, the larvae 

 have been bred from fungi and from hen manure. 



