1912] Eastern Species of Cerceris 17 
Cerceris fumipennis Say. 
From Washington, D. C., Falls Church, Va., and Fedor, 
Texas. The pygidial area of the female is about two and a-half 
times longer than broad, broadest near base, and much nar- 
rowed to the tip. In male this area is more than twice as long 
as broad, the sides nearly parallel, and as broad at tip as any- 
where. The hair-lobes are nearly one and a-half times their 
breadth apart; the last joint of antenne is as long as preceding, 
slightly tapering and somewhat curved. 
Cerceris mandibularis Patton. 
From Washington, D. C., and Falls Church, Va., in June. 
It is allied to C. compacta by structures of clypeus; the enclosure 
is very broad and smooth; the pygidial area two and one-half 
times longer than broad, tip about one-half as broad as in 
middle, the sides strongly curved, the base very narrow. 
Cerceris robertsoni Fox. 
From Falls Church, Va., and Southern Pines, N. Car., in 
June and July. The pygidial area of the female is about two 
and a-half times longer than broad, broadest near base, about 
one-half as broad at the rounded tip, the sides curved. In the 
male it is about twice as long as broad, and plainly narrower at 
tip than elsewhere; the last joint of antennz is as long as the 
penultimate, a little curved, but not concave behind; the hair- 
lobes are fully three times their breadth apart; the clypeus 
very hairy. 
Cerceris compacta Cress. 
This is the most common species in Virginia, and occurs 
from June to September; also from Southern Pines, N. Car., 
and Lee County, Texas. The pygidial area of female is nearly 
twice as long as broad, broadest near base, narrow at tip, the 
upper part of sides strongly curved. In the male this area is 
hardly one and a-half times longer than broad, broadest at 
base; the last joint of antenne is barely longer than the preced- 
ing, tapering, but not concave behind. The hair-lobes are fully 
twice their breadth apart, the lower part (in fact all) of face is 
very hairy; in both sexes the stigma is plainly darker than the 
cell beyond it. In the female the front tarsi are broader and 
more flattened than in any other species. Cameron's figure 
shows that C. mexicana is perhaps the same species. 
