1865.] 20H 



coarsely rugose, the two becoming confluent on the disk in a large de- 

 pressed and coarsely rugose space; scutellum sparsely punctured with 

 a deep, broad, arcuated excavation in front, which has five short sharply- 

 defined longitudinal carinse; metathorax rugose or somewhat reticu- 

 lated, with several well-defined longitudinal carinse ; tegulre piceous. 

 Wings fuliginous, with a slight violet reflection ; nervures and stigma 

 black. Legs, including the coxae, entirely fulvo-ferruginous, the pos- 

 terior tibiae and tarsi tinged with dusky, their femora simple. Abdo- 

 men subsessile, depressed at base, broad and subcompvesscd at tip, 

 smooth and polished, except the basal segment which is densely and 

 rather finely rugose; the second segment is finely aciculate on each 

 side at base ; ovipositor as long as the body, ferruginous, valves black- 

 ish. Length 5 lines; expanse of wings 82 lines. 



One specimen. Distinct from the preceding species by the sculpture 

 of the mesothorax and basal segment of the abdomen, also by the color 

 of the wings and legs. 



Genus CHELONUS, Jurine. 



1. Chelonus sericeus, Say. 



Sigafphus sericeus, Say, Long's 2nd Exp. ii, p. 321. 

 Chelonus sericeus, Say, Bost. Journ. i, p. 266. 



Three specimens. 



2. Chelonus rufiventris. n. sp. 



Black; wings subhyaline : tegulse, four anterior tibiae and tarsi and annulus 

 on posterior tibijc, testaceous ; abdomen dull rufo-ferruginous. 



Male.— Black, opaque, densely rugose, very finely and sparsely pu- 

 bescent; face transversely striated ; tips of mandibles piceous; antennas 

 entirely black, longer than the head and thorax, slender at tips. Thorax 

 more coarsely rugose than the head; spaces on each side of the scutel- 

 lums striated, with an intervening flattened, smooth and highly polished 

 space; metathorax short, abruptly truncate behind, coarsely rugose or 

 somewhat reticulated, the posterior truncation bounded above by a well- 

 defined carina, and has on each side a subacute tubercle ; tegulae pale 

 testaceous, dusky on the outer margin. Wings subhyaline, tinged with 

 yellowish-fuscous ; the nervures as in sericeus, with the second submar- 

 ginal cell more elongate, and its outer nervure obliterated. Legs piceous- 

 black ; tips of the femora, the four anterior tibia? and tarsi, a broad 

 annulus on the posterior tibiae and the base of their tarsi, testaceous. 

 Abdomen broadly rounded behind, dull rufo-ferruginous, slightly va- 

 ried with dusky above towards the base, where the surface is covered 

 with irregular longitudinal rugae, the rugosity becoming very fine and in- 



