1912] The Pezomachini of North America 133 
Thorax elongate and cylindrical, ferruginous, mesothorax and por- 
tion of ‘‘metathorax”’ behind the carina dusky ferruginous; surface 
shagreened, with a.very sparse pubescence. Wing rudiments white, 
scutellum tuberculate. ‘‘Metathoracic”’ carina complete but poorly 
defined, feebly sinuous. Legs elongate and fuscous basally, all tarsi 
mid- and hind-femora and tibiz piceous. 
Petiole but little expanded, elongate, ferruginous, finely shagreened 
and sparsely pubescent. Spiracles sub prominent. Apex about twice as 
wide as the base, and one-third the length of the petiole. Remainder of 
abdomen elongate, black, rather coarsely shagreened and with a 
moderately dense pubescence. Claspers small. 
Observations. Described from a single & specimen taken by 
Mr. William M. Mann from the nest of Formica subpolita 
Mayr. at Pacific Grove, California, June, 1909. 
This species much resembles P. macer Cress. but has much 
shorter antennz and the abdominal coloring is quite distinctive. 
From P. ottawensis Harr. it is distinguished by the much 
more elongate petiole, and differently colored abdomen. 
Pezomachus nigrofuscus sp. nov. 
Male. Length 4.5 mm. wingless, slender; head black, thorax and 
petiole fuscous; remainder of abdomen black with the exception of an 
apical yellow band on the second segment, moderately dense 
pubescence. 
Head from above black, finely rugose and with a moderately dense 
pubescence; the small lateral ocelli are as far from the median ocellus 
as from the eye margins. Antenne about 22-jointed, scape fuscous; 
flagellum piceous above, but with numerous small silvery longitudinal 
lines on each segment, which have the appearance of white hairs. Ven- 
trally the fifth to the ninth flagellar segments are somewhat fuscous. 
Face below the antennz somewhat swollen and lighter in color, malar 
lines distinct, short, hardly more than one-fourth as long as the face is 
wide at the lower angles of the eyes. Clypeus and cheeks piceous; 
mandibles yellowish with piceous teeth. 
Thorax long and cylindrical; entirely fuscous, ‘“‘metathorax’’ some- 
what darker than the mesothorax, and more sparsely pubescent. Wing 
rudiments large and white; scutellum tuberculate; ‘‘metathorax”’ 
rather coarsely shagreened, carina incomplete on median area but well 
defined laterally, fore and mid-legs entirely fuscous, hind femora and 
tibize more piceous. 
Petiole but little expanded, spiracles not very prominent, surface 
shagreened, with a sparse pubescence, color fuscous with an indefinite 
yellowish apical band. Remainder of abdomen slender, piceous black, 
except for a yellow apical band on the second segment, surface rather 
coarsely shagreened and with a moderately dense pubescence. Claspers 
small. 
