70 Harry Scott Smith 
color, and are smaller than Fox’s description would indicate, 
otherwise they seem to coincide fairly well, but may possibly 
represent a distinct species, as I have seen no authentic specimens 
of cressonu, 
Mimesa mandibularis, n. sp. 
2. Length 7 mm. Insect entirely shining black, sometimes with a faint 
bluish cast; pubescence golden and fulvous; occiput and cheeks with fine, 
fairly close punctures, those on the latter slightly the smaller; front and 
disk of clypeus punctured as occiput; longitudinal facial carina distinct, 
extending to anterior ocellus; just behind each posterior ocellus is a small 
depression; distance between the posterior ocelli two-thirds that from the 
ocelli to the nearest eye margin; clypeus strongly convex, bare on the disk, 
quite strongly produced anteriorly forming four indistinct obtuse teeth; 
mandibles black, tips slightly reddish and bidentate, broad basally, scrobe 
with irregular punctures; antennae black, flagellum with a brownish ap- 
pearance, scape strongly punctured in front. Pronotum finely and closely 
punctured above. Mesonotum with punctures fine, indistinct, and widely 
separated, just in front of scutellum deeply longitudinally striate; meso- 
thoracic epimeron strongly carinated anteriorly, mesopleura indistinctly 
striato-punctate; scutellum sparsely punctured on disk, more closely so 
posteriorly, similar to postscutellum; metanotum with a small semitrian- 
gular depression centrally which is smooth within, remaining portion with 
coarse longitudinal rugae; posterior face of metathorax coarsely irregu- 
larly reticulate, lateral faces striate rugose. Petiole about as long as hind 
femur, trisulcate above, bisulcate on each side, gently curved. Abdomen 
elongate ovate, microscopically punctured, narrow margins of apical seg- 
ments slightly testaceous; first ventral segment finely punctured, venter 
with short, sparse golden pubescence; pygidial area almost three times as 
long as broad at base, faintly margined and slightly depressed, with about 
a dozen large deep punctures or pits, and entire surface extremely mi- 
nutely punctured. Legs black with fulvous pubescence, tibial spurs white. 
Wings smoky, iridescent, nervures black; second cubital cell narrowed at 
least one-half above and receiving both recurrent nervures below, each at 
about one-fourth of the entire width of cell from the corners. 
6. Unknown. 
Type, Glen, Sioux county, Nebraska; altitude 4,000 ft., Au- 
gust 21, 1906 (P. R. Jones). This species is apparently related 
to miger. In Fox’s synopsis (Transactions of the American En- 
tomological Society, xxv, p. 1) it runs to dicotomy 5, but the 
clypeus is bare and the front is covered with golden pubescence 
instead of silvery. Differs also from niger in the puncturation 
and shape of anterior margin of clypeus. 
392 
