68 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



latter more thinly covered with velvety brown dust. Cheeks long, lobe- 

 shaped, dependent, covered with silvery white dust. Postocular cilia black 

 above, white below. Thorax metallic green, obscurely vittate with cupreous, 

 thickly covered with brown dust. Scutellum cupreous, more shining than 

 the thorax. Abdomen but slightly compressed dorsoventrally, scarcely 

 longer than the thorax, shining metallic green, with violet and cupreous 

 reflections, segments with rather sparse white hairs. Hypopygium slightly 

 projecting; posterior edge of fourth sternite rather prominent; appendages 

 short, thick, brown, covered with short hairs. Venter, pleurae and coxae 

 metallic green, with a covering of grayish dust, which is so thick on the 

 metapleurae and coxae that the metallic ground-color is completely hidden; 

 fore coxae with white hairs on their anterior surfaces. Legs metallic cupreous 

 green; tarsi black, with enlarged claws and dilated flesh-colored pulvilli. Fore 

 femora with two irregular rows of black spines on their lower anterior sur- 

 faces. Fore tibia with a row of black tooth-like spines, scarcely longer at 

 the distal than at the proximal end, inserted obliquely throughout. Wings 

 grayish hyaline. Venation normal; veins black, becoming honey yellow 

 towards the base; costa becoming suddenly black before the middle of the 

 distance between the tips of the first and second veins. Halteres and tegu- 

 Ise yellow, the latter with white cilia. 



Female. Length 4-4.5 mm.; length of wing 6 mm. Closely resembles 

 the male both in coloration and in the spinulation of the fore femora and fore 

 tibiae. The sternites of the venter are flattened, the pulvilli not dilated. 



Two males and three females from Magdalena, N. Mex., 

 collected by Mr. A. W. Snow. 



69. Hydrophorus sodalis, sp. nov. 



Plate IV, Fig. 122. 



Male. Length 2.5 mm.; length of wing 3-3.5 mm. Proboscis and palpi 

 black. Face of moderate width, with a median longitudinal depression 

 above; lower two-thirds thickly covered with silvery white dust, upper third 

 rather shining, except near the orbit, where it is obscured by a thin layer of 

 yellowish dust. Antennae black, of the usual form. Front cupreous, appear- 

 ing opaque in some lights. Postocular cilia black above, silvery white or 

 light yellow and abundant below. Cheeks broad, lobe-like, dependent, cov- 

 ered with white dust. Occiput, thorax, scutellum and abdomen cupreous or 

 metallic green; the thorax subopaque with brownish dust, the abdomen not 

 longer than the thorax, in some specimens distinctly shorter, rather thick, 

 obliquely truncated behind. Hypopygium black, almost completely con- 

 cealed; sternite of fourth segment projecting, its posterior edge V-shaped. 

 Venter, sides of abdomen, pleurae and coxae thickly covered with white dust, 

 so that the cupreous or metallic green ground-color is almost completely 

 concealed; fore coxae with some yellowish, bristle-like hairs on their fore 

 faces. Legs metallic green with cupreous reflections; tarsi black; pulviUi 

 and empodia moderately enlarged. Fore femur with numerous black spines 



