142 HYMENOPTERA. 



marks exceedingly broad, filling lateral areas but not broadening 

 above insertion of antennse as in the preceding species, extend about 

 half the length of scape above antennal sockets, uniform in width, 

 ending almost abruptly ; clypeus about 2.5 times as broad at apex as 

 at base, and only two-thirds as wide at base as lateral areas at that 

 level ; supraclypeal mark long and narrow, not extending above an- 

 tennal sockets ; yellow on collar restricted to a narrow spot on each 

 side. Tegulse, tubercles and wing bases with more or less yellow. 

 Anterior tibias in front, base and apex of middle and hind tibiae, and 

 all basitarsi yellow; other tarsi brownish. 



Genitalia. — Armature rather slender ; cardo quite short and broad ; 

 stipes with broad superior lobe and slender apex, hairy ; sagittal rods 

 normal, (fig. 21). Seventh ventral plate without teeth, largely mem- 

 branous; wings broad, hairless except for narrow small lobe, (fig. 58). 

 Eighth ventral plate long ; basal part normal ; distal pedicel rather 

 narrow, ending in two flap-like apical lobes covered with long hair, 

 (fig. 64). 



Female. — Larger than male, but puncturation similar in general ; 

 occiput almost impunctate, and abdomen usually quite impunctate. 

 Face broad; lateral marks very narrow, short stripes, (fig. 117); tho- 

 racic markings small and inconspicuous ; legs dark, except base of hind 

 tibiae. 



Habitat. — Rocky Mountain States, and westward ; speci- 

 mens in the collection represent Colo., Wyo., Nev., Calif., 

 Neb., S. D. and N. M. Type locality, Chambers Lake, Colo. 

 9500 feet. Recorded on Solidago and Cleome. Nine male, 

 and ten female specimens examined. I have taken this 

 species in the foot-hills of the Big Horn Mts. in Wyoming 

 at about 4000 feet ; F. S. Bichowsky has taken it in King's 

 River Caiiyon, Calif., at 8000 feet; and Townsend has taken 

 it in the White Mts., N. M. at 6600 feet. 



The few specimens at hand show comparatively little varia- 

 tion in the male, except in puncturation of the abdomen ; in 

 some specimens the entire dorsum is heavily punctured, 

 while the original description of the male states, "first seg- 

 ment of abdomen minutely but distinctly and rather closely 

 punctured ", so evidently that is the typical form. Altitude 

 has apparently no effect on the puncturation for specimens 

 from 4000 and 8000 feet are alike in this respect. Among 

 the female specimens there is considerable variation ; the 

 lateral face marks being very irregular in some, but always 



