124 [August 



white ; the enclosed basal space of the metathorax covered with dense 

 longitudinal strige, and a deeper one down the middle. Wings sub- 

 hyaline, darker on the apical margins and in the marginal cell ; ner- 

 vures fusco-ferruginous. Legs black ; extreme tips of the four an- 

 terior femora, their tibife in front, and a line on the posterior tibiae be- 

 neath, yellowish; the anterior tarsi pale ferruginous, the posterior pair 

 dusky. Abdomen : the basal segment with a transverse yellowish- 

 white spot on each side at tip, the four following segments each with 

 an uninterrupted subapical fascia, narrowed in the middle anteriorly ; 

 beneath entirely black. Length 5 — bh lines; expanse of wings S — S^ 

 lines. 



Variety 9 • — The antennae, collar and metathorax immaculate ; the 

 ^'ascias on the abdomen very narrow, and uninterrupted on the fifth 

 segment. 



Hdh. — Canada West (Saunders) ; Rocky Mountains, Colorado Ter- 

 ritory (Ridings); " Nova Scotia" (Smith). Coll. Ent. Soc. Philad. 



Three $ specimens; % unknown. 



17. Cerceris dentifrons, n. sp. 



Black ; sides of face, base of mandibles, two spots on collar, postscutellum, 

 tibiae, and narrow fasciae on abdomen, yellow; clypens with a large, acutely lu- 

 nate projection; wings subhyaline, dusky at tips. 



Female. — Deep black, strongly punctui-ed, slightly pubescent; the 

 clypeus with a large acutely lunate projection, proceeding from its 

 base, and shaped like that of C. hiiotgulata described above; sides of 

 the face, two dots on clypeal projection, confluent in one specimen and 

 wanting in another, and the base of the mandibles, yellow; antennae 

 black, the flagellum fulvo-testaceous beneath. Thorax : a transverse 

 spot or dot on each side of the collar, spot on tegulae, and the postscu- 

 tellum, yellow; mesothorax and scutellum sparsely punctured; the 

 enclosed triangular space at the base of metathorax longitudinally stri- 

 ated. Wings subhyaline, faintly violaceous, the apical margins and 

 marginal cell, pale fuliginous; nervures dull ferruginous, the stigma 

 paler. Legs : coxae, trochanters and femora except tips, black ; tips 

 of femora, the tibia; within, and the four anterior tarsi, fulvous; tibiae 

 yellow exteriorly ; tips of the posterior tWvx. and their tarsi, dusky. 

 Abdomen with a narrow subapical fascia on each segment, except the 

 last, slightly narrowed in the middle anteriorly, a little interrupted on 

 the first segment, and rather broadest on the second ; beneath black, 

 immaculate. Length 4J — 5 lines; expanse of wings 7 — 8 lines. 



Hah. — Xesv York (Angus) ; Illinois (Dr. Lewis). Coll. Ent. Soc. 

 -Philad. 



