380 
[February 
has two large spots, emarginate outwardly, instead of ‘Hwo central 
oblique stripes.” I see no variation in the markings of the three speci¬ 
mens before me. 
8. A. interruptum, Say. 
Megachile interrupta Say, Long’s 2nd. Expedition, ii, p. 351. 9 (1824). 
Male. —Body punctured, above glabrous; head black; antennae, 
first joint at base and third and fourth joints dull rufous; hypostoma, 
broad frontal orbits, and mandibles at base, yellow; vertex with a fer¬ 
ruginous band, interrupted in the middle and extending down the 
cheeks; labrum rufous, a small black spot at base ; thorax black, sur¬ 
rounded by a ferruginous margin, which is interrupted before, and 
passes upon the posterior margin of the scutel; wings fuliginous; 
pleura with cinereous hair beneath the wings; feet rufous, tarsi with 
yellow hair; terguni convex, black, with dilated, obscure, rufous, 
scarcely definite bands, five in number, on each side of which, except¬ 
ing the basal one, is another yellow band emarginate each side behind, 
and the three posterior ones are interrupted in the middle; anus tri- 
lobated; lobes yellow, intermediate one small; posterior coxae each 
with a robust yellow spine; venter with transverse bands of long, 
dense, yellow hair. Length nearly two-fifths of an inch. 
“ Female. —The black color of the front extends down upon the 
middle of the hypostoma nearly to its tip; the rufous color on the 
basal joints of the antennae is obsolete; labrum black on the disk; 
mandibles black, excepting a small, rufous spot at base; the three last 
bands of the tergum are destitute of any rufous color about them; 
venter densely covered with hair: mandibles as in the male, three¬ 
toothed ; posterior coxae unarmed. Length about the same as the male, 
but more robust. 
“ Hah. —Missouri.” 
This and the two following species are unknown to me, and may 
not belong to this section, but from their description I should judge 
that they did. 
U. A. jugatorium, Say. 
Megachile jugatoria, Say, Long’s 2nd Exped. ii, p. 352, 9 (1824.) 
‘■'■Female. —Body punctured, above nearly glabrous; head with a 
yellow line on the superior part of the cheeks; hypostoma with a di¬ 
lated, yellow line, which extends upon the anterior orbits nearly to 
