366 Dr. A. S. Packard, Jr's Revision of the 



region is broad, but the two lateral pieces very short, though broad, 

 while the clypeus is loug, very slightly truncated and raised before the 

 euiarginate edge, being two-thirds as long as broad, and deeply convex 

 in front, edge smooth, not indented ; mandibles long, slender, second tooth 

 nearly obsolete. Palpi slender, joints scarcely flattened, terminal joint 

 cylindrical, much as usual. The antennae are small and cylindrical, 

 short, second joint subclavate, swelled slightly, beneath full and slight- 

 ly angulated longitudinally; terminal joint not dilated, joints hardly 

 longer than broad. The hind femora and tibiae differ in having the 

 tibial spur much smaller, and the tibiae more spinulated, and in the 

 longer tarsi. 



Those from Illinois differ a little from the Pennsylvanian specimens 

 in having the meta-scutellum yellow, on the femora a mesial yellow 

 line, on each side a small, black, broad stripe, tarsi brown, a pair of la- 

 teral and yellow spots on each side of the basal ring of the abdomen, 

 scape almost entirely yellow, orbital and clypeal region silvery; mandi- 

 bles entirely black; middle femora yellow at tips and beneath, black in- 

 stead of brown, and tibiae entirely yellow ; mesothorax with a very long, 

 silvery pubescence. 



Thyreopus cingulatus, n. sp. 



% . Head black, very finely punctured; clypeal region silvery, a 

 narrow Hue of silvery pubescence extends along the eyes, nearly half 

 way from the clypeus to the ocelli ; antennae black, the two basal 

 joints entirely yellow; thorax black, an interrupted yellow stripe on 

 the prothorax, tubercle yellow; tegulae testaceous, concolorous with the 

 nervures; two small, yellow dots on the meta-scutellum. Enclosure 

 of propodeum sublimate, with six raised longitudinal striae and trans- 

 verse acute rugae between them, the two mesial strias converging pos- 

 teriorly ; on the posterior part the parallel longitudinal striae are bound- 

 ed by raised crests, with transverse rugae. Fore legs yellow, tibiae 

 dilated externally, but not greatly thickened, with a curved brush of 

 fine hairs along the whole length of the joint, a similar line of hairs 

 along the flanks of the thorax above the insertion of the legs; middle 

 pair of legs entirely yellow, hind legs with the trochanters black 

 above; yellow beneath, a slight longitudinal black streak on the upper 

 side of the coxae; femora yellow beneath and on the sides, black above 

 and at tip on the sides, terminal half of the tibiae black above, form- 

 ing an ovate spot ; tarsal joiuts yellow, with a broadstripeon the upper 

 side of basal joint; on the succeeding rings, a pair of broad, large 

 spots, nearly meeting on the mesial line; on hind margin of each of 



