1879.] 143 (Patton. 
thorax punctured; a smooth spot on the disk of the mesothorax, a 
smooth impressed line on each side of the disk and a similar line 
extending anteriorly in the middle. Angles of the prothorax slightly 
produced; anterior coxae produced into a spine at the tip. Meta- 
thorax reticulated at the base, the sides punctured, the punctures 
coarser above. Abdomen convex, as wide at the base as in the 
middle, distinctly punctured. The four basal segments with a nar- 
row continuous fascia of appressed white pubescence; the scattered 
pubescence on the first and second segments white, that on the other 
segments fuscous. ‘The venter more pubescent than usual in Colletes, 
this pubescence tufted on the disk and retaining pollen as well as 
that upon the trochanters, femora and tibiae of the posterior legs. 
Wings hyaline, nervures testaceous. 
Waterbury, Conn., July 12, on the flowers of Heuchera Americana L. 
A less perfect specimen (Waterbury, June 30,) has no distinct 
sculpture on the labrum, and the abdomen, owing to a different degree 
of contraction, is less convex; there is also seen to be a triangular, 
highly polished pit on the posterior face of the metathorax, beneath 
which are two other pits and above which is a polished space. 
The long spine on anterior coxae, the cleft tarsal claws and the 
hairy venter are characters in which this differs from all other species 
examined. In the 2 of armata and americana the spine on the 
coxae is less developed, and in the 2 of compacta and inaequalis and 
in the ¢ of all the species the coxae are merely angulated. In C. 
ciliata sp. n. the tarsal claws are not so evenly cleft, and in inaequalis 
Say the venter is not so pubescent: those being the species which 
most closely approach aestivalis in these characters. 
Colletes armata sp. n. 
@. Syn. C. inaequalis Cress., Proc. Bost. Soc. Nat. Hist., x11, 166 
(1868): nec Say. 
¢. Length 9 mm. Black, the pubescence white, that on the 
thorax above ochraceous. Space between eye and mandible less 
than the width of the eye, base of the labrum with a central enclosed 
pit and two or three less distinct pits on each side of it; clypeus con- 
fluently punctured, at the apex polished and irregularly punctured; 
vertex densely punctured, opake. Prothoracic spine prominent; 
mesothorax deeply punctured, the disk shining and more sparsely 
punctured, anteriorly a faintly impressed median line free from punc- 
tures. Base of metathorax with a transverse series of regular 
reticulations, the posterior face coarsely and irregularly reticulated, 
