4>! [May 



The coloring of the body is usually black, mixed with ferruginous, so that 

 the black prevails on the thorax, the ferruginous on the abdomen, which, in 

 most specimens, has a black, more or less extended, dorsal stripe. Among five 

 males one had a black abdomen, the hind margins of the segments tinged with 

 yellowish and some ferruginous spots on the sides of the two first, on the two 

 last segments and on the club. When the tliorax is black, there is a percep- 

 tible dull tawny sj)ot above the middle eoxte and a dull reddish spot on each 

 side of the metathorax. In some specimens, the reddish color prevails on the 

 thorax so as to leave only three broad, black, shining stripes on its back. The 

 only female which I have seen, had a ferruginous thorax, with the exception 

 of dark spots on the pleurse. 



Anteunse of the male black at the base, flagellum grayish-brown in some spe- 

 cimens, yellowish-white in others, with three rows of branches, the interme- 

 diate one being the shortest. Antennte of the female longer than head and 

 thorax together; three first joints brownish, the following ferruginous, more 

 or less tipped with brown ; the proportion between the length of the joints is 

 the same as in the female of C. fumipennis. On the thorax, the membrane be- 

 tween the root of the wing and the collare is bright yellow : the pleuraj have a 

 slight grayish down. Halteres yellowish, their stem sometimes infuseated. 

 Male genitals large, clavate: female ovipositor long, sword-shaped. Femora 

 ferruginous, dark brown at the tip : fore tibiae dark tawny, still darker towards 

 the tip: middle and hind tibiae ferruginous-tawny, darker at the basis and grad- 

 ually infuseated towards the tip. Tarsi dark brown, the tip of the first joint and 

 the three following joints of the foremost ones are i)ale grayish brown. (The 

 only female specimen liad altogether ferruginous feet, except the tarsi, which 

 were brown, from the tip of the first joint.) Wings with a somewhat topazine 

 yellowish tinge ; veins brown ; the interval between the costa and the first 

 longitudinal vein more saturate yellow; stigma dark brown: its anterior por- 

 tion sometimes paler; one of the males had a rather indistinct small grayish 

 cloud, occupying the latter two-thirds of the discal cell and somewhat encroach- 

 ing upon its surroundings; the extreme apex of the wing is also slightly mar- 

 gined with gray : the second and third longitudinal veins are nearly parallel 

 and the distance between their tips is somewhat shorter than the distance be- 

 tween the tips of the third and of the following veins. 

 Hah. Virginia (Dr. Wilson.) 



Obsfrvation. — I would take this species for C. dorsalis Walker, if it 

 was not for the words : feelers having alternate rows of long and short 

 hranrhrs on each side, which place Mr. Walker's species in the first 

 section. 



C, frontalis n. sp. %. 



Ferruginea, capite nigro. abdominis segmentis 2-S superne nigricantibus. alis 

 liyalinis, stigmate fusco. 



Ferruginous, head black, the segments 2-8 of the abdomen blackish above : 

 wings altogether hyaline ; stigma brown. 



Long. Corp. % 0.(3 : long. al. 0.5. 



