Vol. IX] VAN DUZEE— NORTH AMERICAN MEDETERVS 261 



Descriptions of New Species 

 1 . Medetcrus f alcatus, new species 



Male and female: Length 1.75 mm. Face and front covered \vith gray 

 pollen ; antennas black, third joint small, slightly emarginate at tip where 

 the arista is inserted ; orbital cilia white ; thorax bronze black but so 

 thickly covered with gray pollen as to conceal the ground color and appear 

 gray in unrubbed specimens, without distinct vifctae ; bristles above the fore 

 coxae small, white ; scutellum with two bristles and two small hairs on 

 the margin ; abdomen dark greenish, obscured with gray pollen ; hypopyg- 

 ium of male black, shining, rather thick; its appendages small, yellowish; 

 coxae and femora black; more or less of the femora apically, the tibiae and 

 tarsi yellow, the tips of the tarsi darkened; hind tibiae somewhat enlarged 

 at tip with a short, stout, hooked spur, in the female the hooked spurs are 

 wanting; second joint of hind tarsi a little longer than the first; tegulae, 

 their cilia and the hakeres yellow; wings hyaline, slightly gray, with yel- 

 lowish veins ; distal segment of fifth vein more than one and a half times 

 as long as the cross-vein. 



Described from four males and ten females taken by me at 

 Fresno, Cal., May 6, 1915, while sweeping alfalfa in the park; 

 and one male taken at San Francisco, Cal., May 22, 1915. 



Holotype, male (No. 512), from Fresno, in collection of the 

 California Academy of Sciences. Allotype, female, in collec- 

 tion of the author. Paratypes in both collections. 



2. Medeterus similis, new species 



Male and female : Length 2.2 mm. Face rather wide, covered with gray 

 pollen, below the suture more shining and black with slight greenish 

 reflections ; front covered with gray pollen ; antennae small, black ; pro- 

 boscis of moderate size, shining black with yellow hairs ; thorax covered 

 with gray pollen leaving only a median, shining, bronze-brown vitta 

 which extends to the hind margin of the scutellum when viewed from 

 behind; acrostichal bristles small, in two rows; scutellum with two 

 bristles ; bristles above fore coxae very small, white ; abdomen black with 

 a very slight green tinge, shining but somewhat dulled with gray pollen, 

 its hairs pale ; coxae and femora black ; fore coxae with rather long white 

 hairs ; about the apical third of femora tibiae and most of the basal two 

 or three joints of the tarsi yellow; tarsi blackened towards the apex; hind 

 tibiae a little enlarged at tip and with bent claw-like spurs; second joint 

 of hind tarsi more than one and a half times as long as the first; tegulae, 

 their cilia and the halteres yellow; wings slightly tinged with gray; veins 

 black ; last section of the fifth vein a little more than one and a half times 

 as long as the cross-vein. 



Described from three males and five females taken by me at 

 Los Angeles, Calif., Apr. 27, and May 1, 1915, and one male 

 taken at Fresno, Calif., May 6, 1915. This is closely related 

 to f alcatus, new species, but has the second joint of hind tarsi 

 more than one and a half times as long as the first While in 



