1947] 
CercericlcB 
19 
apart, from side the clypeus is evenly convex; enclosure 
mostly smooth and shining, sides punctate ; basal segment 
of abdomen much broader than long, fully one-half the 
apical width of second segment, the abdomen rather 
broad ; pygidium very broad, hardly one and a half times 
longer than broad, tip truncate, sides somewhat convex; 
the hind tibiae are more swollen toward tip than usual, and 
the outer spines are very prominent. 
Length 10.5 mm. 
From Colton, Calif. (Pilate), Eddy Collection, 24 Au- 
gust and 4 September, and Claremont, Calif. (Baker). 
One specimen from Colton is only 8 mm. long. Tvpe 
M.C.Z. no. 23593. 
Cerceris arno sp. nov. 
Female. Largely yellowish, face wholly, basal half of 
the mandibles, and basal joint of antennae, yellow ; vertex 
with a yellow spot each side from top of eye toward the 
middle, a very large yellow spot back of eye. Pronotum 
wholly, tegulae, a spot below it, yellow, below latter is a 
rufous stain; scutellum, postscutellum, and most of the 
sides of propodeum yellow, leaving only a median dark 
stripe and this is partly rufous ; basal segment of ab- 
domen reddish at base, rest yellow, broad bands on next 
four segments, that on second with a median dark spot in 
front, the third and fourth acutely emarginate in front 
with dark, the fifth entirely yellow ; the terminal segment 
yellow, except the rufous to brown pygidium; venter al- 
most wholly yellow, some segments narrowly dark at 
base; legs almost wholly yellowish to rufous, the tarsi, 
especially the hind tarsi, darker, and a faint dark mark 
at tip of hind tibiae. 
Wings yellowish hyaline, yellow-brown in front, stigma 
yellowish. 
Face with much silvery white hair, not very long, but 
dense, moderately short hair on vertex, thorax, and ab- 
domen. Punctures dense, but not coarse. Mid lobe of 
clypeus somewhat swollen above, much broader than high, 
below with a broad truncation; enclosure mostly trans- 
versely striate; basal abdominal segment much broader 
than long; pygidium nearly three times as long as broad 
