82 J. M. ALDRICH. 



Tachytrechus flori«lensis n. sp. 



M(de. — Front green, heavily coated with whitish dust, face wholly pure white, 

 about twice as wide on the lower division as immediately below the antennge, 

 palpi inconspicuous, proboscis black, inferior and lateral orbital cilia white; an- 

 tenuiB wholly black, the first two joints a little elongate, slender, the third 

 rounded, the arista a trifle longer than the three joints. Thorax green, heavily 

 coated with whitish dust, which leaves the ground-color more distinctly visible 

 in some directions than in others; pleura?, with a more pure white dust, the green 

 showing through ; tegulie and halteres yellow, the former with small black cilia; 

 coxae and basal two-thirds of femora green, overlaid with white dust, the tips of 

 all the femora for a third their length (in the middle ones more) yellow, tibiae 

 yellow with black tips, tarsi black, the front ones four-fifths the length of the 

 tibife; fore tibise with only two series of bristles, three or four in each, the one 

 behind and a little towards the outside, the other opposite in front; hind femora 

 with a row of three bristles before the preapical one. Abdomen of the same 

 color as the thorax, more shining on the posterior part of each segment across the 

 middle, with a rather strong row of hairs before each incisure— these and all the 

 small hairs black ; hypopygium black, the first joint, or pedicel, small ; the second 

 large, massive, sub-globular, with whitish dust and fine black hairs; lamellae 

 blackish, small, somewhat triangular, with a narrow base, the outer edge of each 

 bearing a number of long black bristles extending laterally. Wings slightly 

 grayish, narrow, pointed, with a large black dot in the apex, nearly the whole of 

 which is behind the fourth vein ; third vein almost straight in its whole course, 

 with only a slight and nearly uniform curvature; large cross-vein quite oblique, 

 straight, less than its length from the tip of the fifth vein ; last segment of fourth 

 vein straight, only a very little convergent towards the third, ending conspicu- 

 ously before the apex of the wing. 



Female. — Wings scarcely so narrow, without dot, antennae a little shorter, face 

 a trifle wider. On the outer side of the fore tibiae there are one or two small 

 bristles in a third series. Length 5 mm. ; of wing 4 mm. 



Two males, two females, Florida. Collected by Chancellor F. H. 

 Snow. I obtained the specimens from the University of Kansas, 

 and there are several more in their collection. 



Tachytreclius vorax Loew, Neue Beiti-aege. viii. 41 ; Mon. Do]icho])o- 

 didic, 112. District of Columbia. 



I have specimens from Brookings, S. D. ; Hot Springs, S. D. (in 

 the Black Hills) ; Jackson, Miss. (C. W. Johnson) ; and Franconia, 

 N. H. (Mrs. Slos.son). 



Tacliytrechims aiigiistipeniiis Loew, Centuries, ii, 64; Monograph 

 Dolichopodidae, 113. District of Columbia ; Osteu Sacken, Western Diptera, 315, 

 California. 



I have not seen this species. 



