380 C. rj. OSTEN SACKEN'S PRODROME 



on the soconil segment has the shape of a A, the triangle encompassed by this figure being 

 of the same color as the sides of the abdomen ; the ends of this figure are sometimes (not 

 always) prolonged laterally, along the hind margin, without expanding into small black tri- 

 angles ; segments 3 and 4 are black or brown, with yellow hind margins, expanding into 

 triangles in the middle ; on the black, a yellow spot is often perceptible on each side ; in 

 some specimens the whole of the segments 3 and 4 are yellow, except a double obtriangu- 

 lar spot in the middle, and a small dot, each side, near the anterior margin ; segments 5-7 

 black or brown, with yellow hind margins. Venter yellow at base, blackish at tip ; seg- 

 ments 3 and 4 often with blackish spots in the middle. Legs variable in coloring ; either 

 the prevailing color is yellowish-red, with the tips of front femora, front tibite, the whole 

 hind femora and all the tarsi, except the base, black ; or the prevailing color is black, with 

 the middle tibi«, the bases of front and hind tibiae, and base of the tarsi, reddish. The 

 description of the wings of C. cesfuans applies to this species, with the following differ- 

 ences ; the narrow l)rown Ijorder along the costa, between the crossband and the apex, is of 

 the same shade of brown as the crossband and of the same breadth as the costal border 

 between the crossband and the root of the wing ; it reaches a little beyond the anterior 

 branch of the fork of the third vein ; the gray shade of the apical portion of the wing is 

 much fainter, and hence the white halo along the crossband less distinct ; the fourth pos- 

 terior cell is almost filled out with brown, so that the end of the crossband is much nearer 

 the posterior margin of the wing. 



Uab. NeAV Jersey; Delaware; Connecticut; Detroit, Mich. (H.G.Hubbard); Illinois 

 (LeBaron). Eleven female specimens. The smaller size, the dark, well defined brown 

 border between crossband and apex, the absence of the black triangles encroaching upon 

 the yellow of the second segment, the yellow and not gray, hind border of the abdominal 

 segments, easily distinguish the female of this species from the preceding. 



Male. Two male specimens (Pennsylvania and New York) which I possess, belong, I 

 have no doubt, to this species. The picture of the wings, especially the brown border 

 between the crossband and the apex, is like that of C. callidus, only the two basal cells 

 are filled out with brown up to their distal third, which is hyaline. The brown of the ba- 

 sal cells coalesces with the brown cloud, enveloping the last section of the fifth longitudi- 

 nal vein. The facial callosities are brownish, the middle of the face reddish. Antennae 

 black. The coloring of the thorax is darker, the stripes less conspicuous. The sides of 

 the abdomen are reddish-yellow, which color, in one of the specimens, extends to the third 

 segment ; the yellow triangles on the hind margins of the segments seem a little smaller, 

 but the characteristic yellow hind margins are very distinct, and somewhat broader than in 

 the female. The yellow dots on the back of the third segment are very plain in one of the 

 specimens ; in the other, yellow marks are visible on the fourth segment. 



10. Chrysops delicatulus n. sp. 



9 . Ai»ical spot in the shape of a narrow hnear brown border along the costa, attenuated at the distal end 

 of the stigma; both basal cells hy.iline ; discal cell .almost hyaline; the A-shaped black spot on the second 

 segment broad in its outline ; facial callosities and cheeks black. 



Length, 6.5-7.5 mm. 



