60 
CHARLES ROBERTSON. 
€OL,L,ETES. 
C. spiiio.sa 9- — Black; head short, broad; clypeiis longitudinally striate, 
strongly punctured ; labruni with a small median pit and lateral strife; flagellum 
dull testaceous beneath ; protborax with large, strong, conspicuous lateral spines; 
mesotborax closely and coarsely punctured anteriorly, more sparsely on the disc, 
anteriorly the pubescence is thick and pale, more posteriorly mixed with black, 
thin and black on the disc; metathorax with a single series of subquadrate pits 
on the disc, lateral faces of posterior plate coarsely reticulated ; wings hyaline, 
nervures, stigma and tegulse dull blackish testaceous; legs slender; abdomen 
rather closely and finely punctured, sometimes the punctures appear feeble, basal 
and apical margins of succeeding segments, with fasciae of white pubescence. 
Length 10 — 11 mm. 
% Resembles the female, pubescence longer, prothoracic spine variable, less 
conspicuous than in female, often short, base of second segment not fasciate. 
Length 8 — 9 mm. 
Five females, fourteen males, taken on flowers of Solidago cana- 
densis, S. laneeolata and Polygonum hydropiy^er, August 30th to Oc- 
tober 7 th. 
C. latilarsis 9 . — Black, clothed with whitish pubescence; clypeus bare, 
or nearly so, strongly punctured, with a median longitudinal depression ; labrum 
with a large central depression, striate on the sides ; flagellum testaceous beneath ; 
prothorax with lateral spines evident ; mesothorax closely and strongly punc- 
tured, clothed with short feathery hairs, which are mostly black on the disc, 
whiter around the edges; scutellum with a posterior border of black hairs, which 
are followed behind by white ones; a patch of hairs on the pleura behind the 
tubercles and a few hairs on the vertex also black ; metathorax sharply truncate, 
with a single transverse series of subquadrate pits on the disc; wings hyaline, 
faintly clouded beyoud the marginal cell, nervures dull testaceous, stigma black, 
tegulse black, dull testaceous exteriorly ; legs stout, clothed with pale pubescence, 
mixed with fuscous, especially on the scopse exteriorly; abdomen densely and 
finely punctured, especially on the second segment, third segment more finely 
and sparsely punctured, segments 1-4 with narrow apical fascim of white pubes- 
cence, fifth not fasciate. Length 11 — 12 mm. 
'J, .—Closely resembles the female ; labrum usually not so depressed medially, 
flagellum darker, pubescence longer and paler, punctures a little less dense, an- 
terdor femoi-a ciliate with long white pubescence, basal joint of hind tarsi re- 
markably broad. Length 10 — 11 mm. 
Five females, five males, taken from July 9tli to September 20th, 
on flowers of Asclepias incarnata, Physalis virginana and Polygonum 
hydropiper. It is very abundant on flowers of Physalis. 
Willistoiii 9 . — Clypeus rough, with rather sparse, shallow punctures, 
with a median longitudinal depression ; labrum with five deep grooves; flagellum 
dull testaceous beneath; jn-othoracic spine evident, sharp; mesothorax closely 
and strongly punctured, clothed with thin, pale pubescence, which is strongly 
mixed with blackish on the disc; scutellum with coarse punctures; disc of meta- 
thorax with a transverse series of subquadrate pits ; lateral faces of posterior 
