S. W. Williston — North Arnerieon Conops. 333 



liiiu], a stn|x' in the first Imsal ceil, and tlie base u1' the uiial ceil, 

 pure liyaliiie. The subhyaline tills out a larger part of the Jiscal 

 and first posterior cells ; the stripes along the fifth and sixth veins 

 not so well marked as in excisus, otherwise similar. Long, corp., 

 n_12"""-, long, al., 10""". P'onr specimens, Texas (Belfrage) ; Mass., 

 Conn. 



Two additional nude specimens from Connecticut, differ in their 

 much deeper black, the legs in part, the antennae almost wholly so, 

 the spot above the base of the antenna^ larger, the humei'i and scu- 

 tellum scarcely reddened, and the dust markings throughout are 

 more gra}'. 



Conops tibialis Say. 



Journal Acad. Phil., vi, 171. 



O. nigricm-niii Wied., A\\». Z\v. Ins., ii, 2:56, 4. Loew, Xeue Beitr., i, p. '-M. 



S ? . Face waxy yellow ; cheeks black, with a narrow silvery 

 line near the orbit; facial grooves deep black. Proboscis black, con- 

 siderably swollen at the base. Antenme black; the under sides of 

 the first and third joints somewhat reddish brown ; first and third 

 joints of nearly equal length, scarcely half as long as the second ; 

 process of second joint of style only moderately projecting ; third 

 joint conic, rather short. Vertical callosity nearly black, rather 

 shining, bordered in front by a black, opaque, transverse stripe, con- 

 tinued as a median stripe to near the base of the antennae, where it 

 divaricates Alike on to the sides of the face. Occiput black, dusted 

 with whitish, above posterior orbits with a narrow white line. Tho- 

 rax deep black, with whitish bloom when viewed obliquely; humeri 

 usually concoloroiis, sometimes slightly tinged with red, faintly or 

 not at all dusted with white above; sides of metanotum inconspicu- 

 ously dusted with white. Abdomen black, first and second segments 

 with broader, remaining segments with narrower, posterior yellowish 

 white borders, fourth, fifth, and sixth with white dust above, becom- 

 ing most abundant on the sixth. Legs black, coxa^ with satiny white 

 luster ; trochanters, base and extreme tips of femora, yellowish red ; 

 basal halves of tibicv yellow, distal portions reddish brown ; anterior 

 pairs, on their outer distal portions with satiny white luster. 

 Tarsi : antei'ior pairs reddish, becoming black at tips, hind pair 

 mostly black. Anterior half of the wings dark brown, before the 

 first longitudinal vein not much clearer ; the brown accompanies the 

 fifth longitudinal vein nearly to the border of the wing, then follows 

 . Trans. Conn. Acau., Vol. IV. 44 March, 1882. 



