138 HYMENOPTERA. 



round punctures, not rugose. Enclosure of propodeum broad ; neck 

 narrow; bowl almost entirely covered with broad, shallow, subquad- 

 rate pits ; laterad of bowl a rounded, pitted area extends down on the 

 side; remainder of propodeum rugulose. Mesopleura with large, 

 round punctures, separated by less than diameter of one puncture;' 

 metapleura rugose striate. Dorsum of abdomen almost uniformly 

 punctured, at least first four segments, with round punctures about 

 half as large as those on mesoscutum ; separated by about twice the 

 diameter of one puncture ; on sides and venter becoming more sparse. 



Yellow Markings. — Supraclypeal mark long ; lateral marks confluent 

 with orbit, extending above the insertion of antennae about the length 

 of scape, and broadening above it ; spot on labrum variable. An 

 unbroken line on collar; spots on tubercles, tegulae, and wing bases 

 yellow. Anterior tibiae in front ; middle and hind tibiae entirely, ex- 

 cept ring near apex, and all tarsi yellow, (fig. 109). 



Scape dark, short, broad in front, somewhat flattened (in the figure 

 it is directed upward, appearing abnormally short). Supraclypeal 

 area below insertion of antennas almost quadrate ; clypeus at base 

 slightly narrower than lateral areas at same level. 



Genitalia. — Both the armature and the ventral plates are very similar 

 to those of P. coloradensis and P. polifolii, as shown in the figures, 

 (figs. 23, 55, 67) (see also description under P. coloradensis). The 

 membranous flap of each wing of the seventh ventral plate is peculiar 

 in shape, being somewhat ear-like, and finely lined as shown. The 

 location and shape of this distinguishes the species at a glance. 



Female. — Larger than the male. About 6 mm. long. In punctura- 

 tion it is very similar to the male except that the punctures of mesos- 

 cutum are more dense, and those of pleura more sparse, while those 

 of the abdomen are much smaller and more sparse. The yellow mark- 

 ings resemble those of the male, except on face and legs. The only 

 marks on the face are two long lateral marks which resemble the 

 lateral marks of the male, except that they do not broaden much above 

 antennal sockets, and are truncate instead of tapering at apex. Base 

 of clypeus almost one and one-half times as broad as lateral areas at 

 same level. Tibiae with less yellow than those of male, and tarsi ex- 

 cept basitarsi black. 



Habitat. — So far as known only Arizona and New Mexico. 

 Male and female types from Las Cruces, N. M., " on campus of 

 Agricultural College. Sept. 1894". Recorded on flowers of 

 Mesquite, So/idago, Biglovia and Falhigia during May and June. 



Six males and three females in the collection represent the 

 above localities. In these there seems to be no variation 

 whatever in general characters. The yellow marking of face 

 and thorax, including the unbroken yellow line on collar, are 

 constant in all. Apparently this is a species showing little 



