38 Harry Scott Smuth 
1. Size larger, length 9-13 mm.; face with sparse pubescence; legs 
testaceous and yellow in female, black or piceous and yel- 
low in male; bands narrower and more interrupted. ..frigidus 
Aphilanthops quadrinotatus Ashmead. 
1890. Aphilanthops quadrinotatus Ashmead, Bulletin of the Colorado -| 
Biological Association, i, p. 7. : . 
1898. Aphilanthops quadrinotatus Dunning, Transactions of the 
American Entomological Society, xxv, p. 24. : 
Rather abundant in Sioux county, flying around flowers of 
Solidago about the middle of August. 
Aphilanthops laticinctus (Cresson). 
1865. Philanthus laticinctus Cresson, Proceedings of the Entomolog- 
ical Society of Philadelphia, v, p. 91. 
1898. Aphilanthops laticinctus Dunning, Transactions of the American 
Entomological Society, xxv, p. 22. 
Also abundant at the same time and locality and on same flow- 
ers as above. There is a possibility of this being the unknown 
male of guadrinotatus. 
Aphilanthops frigidus (F. Smith). 
1856. Philanthus frigidus F. Smith, Catalogue of Hymenoptera in the 
British Museum, iv, p. 457. 
1896. Aphilanthops frigidus Dunning, Transactions of the American 
Entomological Society, xxv, p. 20. 
West Point, June (L. Bruner) ; Glen, April 12 (P. Re, Jones)e 
This latter specimen differs from the description in having the 
face entirely yellow below the antennae and in having a large 
yellow spot on the pleura; one of the West Point specimens shows 
the same variation; some of the females as well as the males have 
the venter spotted with yellow. 
Subfamily CERCERINAE 
KEY TO THE GENERA 
Third cubital cell not quadrate, the third transverse cubital vein 
oblique, joining the marginal cell much before the apex; second 
cubital cell petiolate; dorsal abdominal segments 2-6 without a 
median transverse furrow or impression, but usually margined at 
APSR hiro cesiescvosestvche Seakocd apexe Vane Were Stee aA a ee robe Parana he coe eric ae Cerceris 
Third cubital cell quadrate, the third transverse cubital vein joining 
the marginal cell at apex; second cubital cell petiolate in the fe- 
360 
