54 Psyche [April 



Tachydromia enecator Melander. 



Trans. Am. Ent. Soc, xxviii, 226, o (1902). 



Length 3J mm. Totally jet black, shining, except that the knees narrowly 

 and the metatarsi are piceous, the palpi, antennae and halteres are dull black, 

 and the hinder occiput, pectus, metanotum, a narrow vertical stripe on the 

 metapleurae, front coxae, and underside of the front femora are provided with 

 a light pruinose coating. Outer antennal joint elliptical, arista terminal. 

 Humeral swellings of mesonotum large and well marked: no bristles on disc 

 of mesonotum, scutellum with four minute bristles. The S" abdomen 

 depressed, less shining apically, the hypopygium small, terminal, somewhat 

 triangular in outline, it and the last ventral segment provided with short 

 blackish hairs. Wings with two dark cross bands, the second vein append ic- 

 ulate in the known specimens. 



But five specimens are known of this species. The two cotypes, 

 both females, are from Quebec and Wyoming. They are now located 

 in the Wheeler collection at the American Museuin of Natural History, 

 New York City. I have a male and two females, collected by my 

 former student, E. L. Jenne, at Douglas, Alaska, August 2, 1901. 

 This is our largest species. 



Tachydromia schwarzii Coquillett. 



Coquillett, Proc. U. S. N. Mus. xviii. 440 (1895). 

 Melander, Trans. Am. Ent. Soc. xxviii. 225, fig. 52 (1902). 



Length 2.5 mm. Shining black, the legs yellowish. Occiput and pro- 

 pleurae pruinose. Antennae fuscous to black, the outer joint rounded, the 

 terminal arista about four times the length of the antenna. Facets of the eyes 

 nearly uniform, front narrow. Palpi glistening white to dirty white, elongate 

 and slender. Mesonotal disc shining, bristleless, scutellum with four short 

 bristles. Hypopygium moderate, rounded, its curved slender appendages 

 sometimes exserted. Legs including the coxae dusky yellow-, the hind legs 

 darkest, the tibiae and tarsi more or less infuscated. Halteres pale yellow. 

 Wings slender, rather pointed, crossed by two broad brownish fasciae, leaving 

 the base, middle and tip hyaline; the marginal cilia normally short. 



This is a common insect in the West. During the entire summer it 

 hurries about in quick little zig-zag runs in search of its small victims, 

 curiously probing among grass, stones, sidewalks, houses, in fact it 

 can be found almost everywhere in this region. I have seen hundreds 

 of living specimens, and have examined nearly a hundred mounted 

 individuals from Moscow, Idaho, and Pullman and W^enatchee, Wash- 

 ington. The types came from California and Utah. They are 

 numbered 3246 and 3247 in the National Musevmi collection. 



