ALDRICH AND DARLINGTON. 93 



Abdomen yellowish, but nioie or less infuscated ; hypopygium yellow, rather 

 large. 



Legs straw-yellow ; fore femora stout ; last three joints of all the tarsi black. 



Four male ami tliree female specimens. C. F. Baker: Ormsby 

 County, Nevada, July 6th. Aldricli : San Juan Island, "Washing- 

 ton, May 81st ; Juliaetta, Idaho, July 9th ; Moscow, Idaho ; Craig's 

 Mt., Idaho ; Colorado (E. S. Tucker). 



Loew did not identify nevwrum from North America, but named 

 our species assimilis, stating that it did not differ from nemoriim, 

 except in having a little shorter pluraosity of the arista and general 

 paler color; Czerny identified his American material as nemorum, 

 and did not identify assimilis, merely quoting the description (op. 

 cit., p. 222). From these facts I feel safe in making assimilis a 

 synonym of nemorum. 



Helomyza zetlersiedti Loew. 



Length of body 5.6 mm. ; of wing 6.9 mm. 



General color yellow ; wings hyaline. 



Front leather-yellow, lower part pubescent; eyes medium size, round ; cheeks 

 straw-yellow, about two-fifths the width of the eye; antennae yellow, third joint 

 rather large, somewhat infuscated, oval; arista rather long, not plumose, but 

 merely pube.scent ; vibrissse of medium size ; at the base of the occiput is a bunch 

 of small black hairs. 



Tliorax yellow; dorsum clay-yellow, rather sparsely pubescent; the small 

 hairs not arising from dots; mesopleurse clay-yellow, bare; besides one strong 

 bristle a few scattering small hairs on the sterno])leuise ; scutellum yellow, bare. 



Wings entirely hyaline. 



Abdomen blackish yellow, hypopygium of the male bright yellow, rather large. 



Legs yellow, femora lemon-yellow, tibipe and all but the last two joints of the 

 tarsi straw-yellow, last two tarsal joints black, inner side of hind and middle 

 femora glabrous, at the apex of the femur is a black spot on the inner side. 



Fifteen female and eight male specimens. Aldrich : Mt. Consti- 

 tution, Washington, July 7th ; Friday Harbor, Washington, May 

 29th. U. S. N. M. : Popoff Island, Alaska, July 8th. 



Helomyza bsirb«>i*i n. sp. 



Length 5.8 mm. ; of wing 6.3-7 mm. 



General color brown, wings brownish, a brown ring or spot at each end of the 

 hind tibia and at the distal end of the front tibia. 



Head yellowish; front ochre-yellow except a brownish strip running down 

 from the vertex on each side including the fronto-orbital bristles, and a wider 

 brown area in the middle including the ocellar triangle; all the yellow portion 

 of the front pubescent, a strip of small black liairs extending from the ocellar 

 bristles to the vertical bri.stles; antennae yellowish-brown, third joint oval, arista 

 long and slender, only microscopically pubescent. 



Dorsum of the thorax yellowish-brown, wholly pubescent, the small hairs 

 arising from small brown dots, the bristles arising from larger brown spots; in 



TRANS. AM. KNT. SOC. XXXIV. M.\RCH, 1908. 



