352 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxi. 



Sphex costipennis ^hvs,svR^, Keise d. Novara, Hym., 1867, p. 39. 

 Isodontia costipennis Patton, Proc. Bos. Soc. Nat. Hist., XX, 1880, p. 381. 

 Sphex costipennis Cameron, Biol. Centr.-Amer., Hym., II, 1889, p. 35, pi. in, 



fig. 10. 

 Sphex {Isodontia) coslipennis Kohl, Ami. Natur. Hofinus. Wien, V, 1890, p. 382. 

 Sphex (Isodontia) costipennis Fox, Proc. Acad. Nat. Sci. Phila., 1897, p. 375. 

 Sphex [Isodontia) costij)ennis Ducke, Zeits. f. Syst. Hym. u. Dipt., I, 1901, p. 241. 



Bluck or black and ferruo-inou.s, the distribution of these colors 

 vary ino- greatly; with golden pubescence and hairs, varying much in 

 abundance and location; legs usually in part ferruginous yellow; 

 petiole vei-y long; wings quite hyaline, sometimes partly fuliginous, 

 generally distinctly tinged with yellow. 



Female. — Head l)r<xid, not noticea])ly hollowed in front between the 

 eyes; clypeus ])road, extending well downward at the sides, its ante- 

 rior edge refiexed, nearly straight, with a pair of short, tooth-like pro- 

 jections at the center more or less developed, with a median carina on 

 its posterior half; clypeus and frons to the ocelli usually thickly 

 pubescent and ])earing long yellow hairs; vertex and cheeks with 

 many long hairs; cheeks rather more than half the width of the eye, 

 with a narrow band of pubescence just behind the latter; narrowing 

 rather quickly below; scape more or less sericeous and bearing short 

 hairs; first segment of the filament the longest; eyes slightly converg- 

 ing downward; mandibles two-toothed, glistening, generally ferrugi- 

 nous except the base and the tips of the teeth. 



Thora,!'. — Neck very short; collar narrow from front to rear, rising 

 sharply at right angles to the dorsal surface of the neck; the dorsal 

 edge of the collar evenly rounded from side to side, the sides of the 

 collar forming a sharp angle with this edge, which is pubescent; a 

 marked depressed line runs l)ack from the middle (in height) of the 

 anterior face of the collar to near the middle of the base of the pro- 

 thoracic lobe which is pubescent; mosonotum sharply bent downward 

 in front and almost vertical at the sides in front of the teguhv, with a 

 median groove or impressed doubled line extending back from the 

 anterior margin al)out one-third of the length of the plate; surface of 

 the plate quite closely punctured and bearing numerous hairs; scutel- 

 lum rather broad from front to rear, evenly rounded, with a pubescent 

 spot on each hinder corner; postscutellum pubescent, apparently with 

 a faint median impression; dorsum of the median segment closely, 

 rather coarsely punctured, sometimes pubescent; fovea small, slightly 

 crescentic rather than hyphen-like; posterior end from the fovea to 

 the petiole with a iiuadrangular, pubescent spot; sides of the median 

 segment closely punctured and with fine, nearly vertical aciculations; 

 a pubescent band runs from the hind coxie forward and upward below 

 the stigma to the front corner of the dorsum; meso- and metapleura 

 coarsely, closel.y punctured, the latter the least of the two; petiole 



