June, 1912.] AlDRICH : BlOLOGY OF WESTERN EPHYDRA. 85 



Ephydra hians Say. 



Say, Jour. Acad. Sci. Phil., VI, 188, 1830. Original description of adult; 



habitat Mexico; reproduced in Say's Complete Works, II, 371. 

 Loew, Centuries of N. A. Dipt., VI, 88, 1865. Adult described as Ephydra 



crassimana ; habitat Mexico. 

 Packard, Amer. Journal of Science and Arts, 3d ser., I, 103, 1871. Larva, 



pupa and puparium described as Ephydra calif ornica ; habitat. Clear Lake, 



Lake Co., Cal., supposed to be salt water: puparia from Mono Lake 



probably the same. 

 Williston, Transactions Conn. Academy, VI, July, 1883, sep. p. 4- Describes 



adult supposed to be that of calif ornica Pack., from Soda Lakes, Nevada ; 



notes on larvee in these lakes and at Mono Lake, and use as food by 



Indians. 

 Williston, North Amer. Fauna (Bull. 7 Pt. 2, Div. of Ornith. and Mammal., 



Dept. of Agric), p. 257. Adult described as Ephydra tarsata, from 



Owen's Valley, Cal.^ 



Adult (PI. IX, Fig. 18).— Black, opaque gray all over except the front, 

 which is shining dark green; first joint of front tarsus considerably thickened 

 in the male. Front with scattering small hairs except in the somewhat de- 

 pressed middle portion, toward the sides anteriorly with three or four pairs 

 of bristles of different sizes, the largest decussate; the shining part of front 

 narrowed anteriorly, and the opaque sides becoming wider; two vertical 

 bristles on each side, the tips of the inner pair almost meeting; ocellar tri- 

 angle opaque, with three pairs of bristles, becoming smaller posteriorly ; frontal 

 orbit with four curved bristles ; face prominent in the middle, rather densely 

 hairy all over, longest on the lower edge; rather bushy hairs below the eye 

 and behind its lower part; antennae of medium size, first joint distinct, second 

 with an erect hair, third without a lateral hair, arista short, thick at base, 

 nearly bare. 



Dorsum of thorax with plentiful coarse hair, besides the usual bristles ; 

 many of the hairs approach the size of bristles, making the chaetotaxy con- 

 fused — however it is easy to count six dorsocentrals, 3 humeral, 2 presutural, 

 2 large median prescutellar ; scutellum with coarse hair and two pairs of 

 bristles, sometimes another small pair between the main ones; pleura con- 

 colorous, the mesopleura, propleura and sternopleura all hairy, mesopleura with 

 a row of bristles on hind edge, stenopleura with one bristle; metanotum and 

 remainder of pleura bare. 



Abdomen concolorous, the greenish ground-color showing through a little 

 more than on other parts of body, both dorsal and ventral sides coarsely hairy ; 

 hypopygium of male small, generally retracted ; tip of abdomen of female with 

 the usual two spines curved backward below. 



^ In making out the above synonymy I have been aided by suggestions 

 from E. T. Cresson, Jr., and the late Mr. Coquillett, of the National Museum. 

 As will appear, we have to deal with a very widespread form, which has been 

 partially described several times. 



