18 Myron Harmon Swenk 
twice its width or less. Claws dark rufous, medially toothed. Tibial spurs 
short, dark, not distinctly pectinate. Anterior coxae unarmed. Abdomen 
stout, subconical, shiny black, its basal truncation. polished and slightly 
punctured, elsewhere coarsely, densely punctured, densest on segment 2, 
being feebly punctured on apical segments, its-base with short, erect, white 
hairs and apical margins of segments 1-4 with narrow, white fasciae not 
distinctly continued on venter, and very short, inconspicuous pale fuscous 
hairs between. Segment 5 not distinctly fasciate but sometimes with a 
fringe of pale hairs, and together with apex covered abundantly with blacl< 
bristles intermixed with a few shorter pale ones. Apical margin of seg- 
ment 1 and both basal and apical margins of segment 2 more or less de- 
pressed, at least laterally. Venter with long, pale, scattered hairs, denser 
on apical margins of segments. 
dS. Length 10-11 mm. Differs from the 2 as follows: Pubescence 
longer and paler; the clypeus with a few, short, pale hairs, the mesothorax 
with very few dark hairs among the white ones, but the scutellum with a 
conspicuous posterior border of them, the anterior femora with a remark- 
able fringe of elongated, dense white hairs forming a conspicuous beard 
as long as or longer than the joint itself; malar space about one-third as 
long as wide; antennal joints beyond 5 subequal in length and breadth, 
joint 8=5 but exceeding 4, the proportion being 4:3:4; basal joint of hind 
tarsi with its posterior edge lengthened into a stout apical lobe, middle 
joints of hind tarsi as wide as long. 
Genitaha.—sStipes notched, its apex long and curved; sagittal rods slen- 
der, straight, moderately spatulate at tips which are not divergent; volsella 
moderate; seventh ventral plate large, the lobes elongate, spoon-shaped, 
the internal costa adherent and densely fringed the entire length of the 
lobe, which has the external terminal portion recurved, the external costa 
modified to form a lateral cordate lobe, purely membranous and with the 
outer half thinly haired. (Plate 1, figures 3 and 3a.) 
Type Locariry.—Carlinville, Illinois; types in collection of 
Mr. Charles Robertson. 
This species is characterized strongly by the great breadth of 
the tarsi postici. Mr. Robertson originally described it from ten 
specimens, half of each sex, taken from July 9 to September 20 
at Carlinville on Physalis virginiana, Asclepias incarnata, and 
Polygonum hydropiper. The season he now gives for the species 
is June 13 to September 29 and records it as visiting chiefly Phy- 
salis. The bee is a common and widely distributed one, ranging 
from the Atlantic coast (Washington, D. C.) west to the Rocky 
mountains (Colorado Springs, Colorado, and Sioux county, Ne- 
braska) and north to southern Wisconsin (Milwaukee). In Ne- 
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