244 Psyche [December 
SOME BEES FROM ELDORA, COLORADO. 
By T. D. A. CockERELL. 
The University of Colorado, Boulder, Colo. 
My wife and I spent the afternoon of August 18 and morning 
of August 19, 1910, at Eldora, in the mountains of Boulder County, 
Colorado. The locality is in the Canadian Zone, at an altitude 
of about 8,550 ft., and has a bee-fauna rather widely different 
from that of Boulder. So many interesting species were collected 
that it seems worth while to put the whole on record. At this 
season of the year, the best bee-plant at Eldora is Grindelia sub- 
alpina Greene, a very fine species which makes the valleys gay 
with its orange-yellow flowers. Less abundant, and much less 
conspicuous is Phacelia leucophylla Torrey, with white flowers. 
These two are referred to by their generic names alone in the 
following list: 
Andrena n. sp. Much like A. hirticincta, but hair at end of female abdomen 
pale. Females rather common at Grindelia; one male on Erigeron. This species 
was named in MS. by Viereck, from specimens collected in New Mexico; it will be 
published in his revision. 
Halictus lerouxii Lep. Both sexes common at Grindelia. 
Halictus ruidosensis Ckll. Both sexes at Phacelia, the males abundant. 
Agapostemon texanus subtilior Ckll. One male at Grindelia. This sex is 
undescribed; it differs from true teranus by its smaller size, the metathorax more 
delicately sculptured, black on legs reduced, and flagellum paler. 
Specodes (Sphecodium) fragarize Ckll., var. a. Female smaller, about 5 mm. 
long, face more narrowed below, middle of abdomen much suffused with black. One 
at Phacelia. This may be a distinct species, but I have only a single specimen, and 
fragarie, as represented by numerous specimens collected at Florissant, is very 
variable. 
Perdita snowii Ckll. Common at Grindelia. This species was described from 
a single specimen collected by Snow in 1892 in Estes Park, Colorado. Later, I took 
a specimen at Santa Fé, New Mexico, but the species has escaped rediscovery in 
Colorado until the present time. The male, which was not known, runs in my 
table in Proc. Phila. Acad. Sci., 1896, to 28, except that there is a small black 
mark or band along each side of the upper part of the clypeus, not on the clypeus 
itself. It runs on to 30, but face is bare, while mesothorax is hairy. The following 
characters are distinctive: Face below antenne bright chrome yellow; yellow in 
median line extending above antennz as a small spear-head shaped mark; at sides 
