98 • AMKRICAN DIPTERA. 



tips; first joint of the tarsi rufous, the following joints blackish; tibiae witli <i 

 preapical bristle. Halteres j-eilow. Wings grayish ; a black border along the 

 costa, around the tip and on the cross-veins, and blackish spots of difl'erent sizes 

 in all the cells; the costa with a row of short bristles; small cross-vein nearly 

 under the end of the first vein, and on the middle of the discal cell. 



"Hab. Mexico, Sierra de las Aguas Escondidas in Guerrero, 

 9500 ft. (H. H. Smith). 

 " Two female specimens." 



AL.L,OI»HYL.A Loew. 



One frontoorbital bristle; five dorso-central, arranged as in Helo- 

 myza ; one humeral ; one propleural ; one presutural ; two notopleu- 

 ral ; no prescutellar ; two pairs scutellar; three supra alar; one 

 sternopleural ; no mesopleural. 



Head as in Ile/omijza, third antennal joint a little elongated, 

 arista pubescent. 



The main distinction between this genus and Helomyza is in the 

 al)sence of the humeral bristle in the latter. 



Only one North American species has been brought to light. 



Allopliyla la»vi>* Loew. 



Length 4.7 mm. ; of wing 5 mm. 



Yellow, autennte of the same color or a little daiker, third joint infuscated in 

 the female; aiista pilose. 



Head yellow; front safl'ron-yellow, with very delicate pubescence, eyes rather 

 large (about twice the width of the cheeks), round; cheeks straw-yellow; 

 vibrisssB very delicate. 



Thorax varying fiom saffron to straw-yellow, densely pubescent; scutellum 

 bare except the ordinary four bristles; mesopleura bare; sternopleura rather 

 sparsely pubescent, with one strong bristle. 



Abdomen yellow, more or less infuscated, hyi)opyginm of tlie male small. 



Wings almost hyaline, unspotted, except a little infuscation around the hind 

 cross-vein. 



Legs straw-yellow, last tarsal joint black. 



Two males and six females. Johnson : Montpelier, Vermont, 

 June 25tli ; St. Johnsbury, Vermont, June 27th ; Mt. Greylock, 

 Massachusetts, June 15th ; Castle Rock, Pennsylvania, June 16th. 

 U. S. N. M.: White Mountains, New flampsliire, Morrison. Ald- 

 ricli : Guemes Island, Washington, July 13th ; Mt. Constitution, 

 Orcas Island, Washington, July 7th. 



KII.I<;0 Aldrich, n. gen. C:^^ ^ -"■"-Xf^^^ 



(Latin, sll'ujo a very pale kind of wheat; feminine, accent on sec. 

 ond sylable.) 



One humeral bristle; one propleural ; two noto[)leural ; five dorso- 



