76 PROCEEDINGS OF THE ACADEMY OF [1896. 



Wings hyaline, nervures sepia-brown, stigma hyaline in middle. 

 The marginal cell is distinctly longer than in bakerce or zebrata, and 

 has the poststigmatal portion longest. Second submarginal large, 

 narrowed one-half to marginal ; 3d discoidal absent. 



Abdomen above with nearly equally broad bands of yellow and 

 black. First segment all black ; then follow four black bands at 

 the junction of the segments, none interrupted, nor joined at the 

 middle or the sides. Tip blackish. Venter yellow, with a little 

 black along the sutures. 



Hab. — Glenwood Springs, Colorado, Aug. 24, 1894. Collected by 

 Prof. Gillette, sent by Mr. Fox. Like the last, taken at the same 

 time, it is reddened by cyanide. It is unfortunate that we know 

 nothing about the habits of this species, and have only a single 

 specimen. It will be recognized by the regular entire abdominal 

 bands, the coloration of the legs, etc. 



A species from California, habitat unknown, S unknown. 

 31. Perdita trisignata n. sp. Fig. 14, (face-marks). 



9 . — Length about bi mm. Head and thorax blue-black or 

 greenish-black, the tint difficult to define. Head of ordinary size, 

 nearly round, somewhat depressed on vertex ; face very sparsely 

 hairy, cheeks not so hairy as in many species. Vertex dull and 

 very distinctly granulose. Middle ocellus in a distinct depression. 

 Mandibles stout, yellowish, with rufous tips and bases. Clypeus 

 brown-black, contrasting with the distinctly green face above it ; in 

 shape high, something like a cocked-hat. Face-markings pale lemon- 

 yellow, consisting of a longitudinal median stripe on clypeus, start- 

 ing from its hind-border but not reaching its anterior border ; and 

 the lateral marks, elongate-pyriform, with the upper end pointed 

 and level with the sockets of the antennse. The clypeal 

 mark suggests that of obscurata. Antennse dark brown. 

 Mesothorax only sparsely hairy, distinctly granular 

 and punctured, the punctures sparse but distinct. 

 Fig 14. Metathorax granular, very dull, duller than scutellum 

 and postscutellum. Pleura hairy, with white hairs. 

 Tubercles and two spots on hind margin of prothorax yellow. 

 Tegulse testaceous, subhyaline. 



Wings rather small, yellowish-hyaline, nervures and stigma tes- 

 taceous. Stigma small and narrow ; marginal cell very large, post- 

 stigmatal portion noticeably longest. Second submarginal large, 

 narrowed more than one-half to marginal ; 3d discoidal distinct. 



