218 SEVENTEENTH Report STATE ENTOMOLOGIST oF MINNESOTA—1918 
nerve centers, rather than stinging their victims. Their nests are provi- 
sioned largely with Diptera, though they also attack caterpillars, 
spiders, aphids and other insects. 
Crabro stirpicola was observed by the Peckhams to work night and 
day for forty-two consecutive hours. 
Minnesota species: Crabro trapezoideus Pack., Thyreopus sp., 
Crabro (Rhopalum) pedicellatum Pack., Solenius (Xestocrabro) sayt 
Ckll. (See col. plate 2.) Anacrabro ocellatus Pack. Unidentified 
species of Crabro were taken by Viereck on aster, golden rod and achil- 
lea, at Itasca Park during Aug. 1913 and in Roseau Co. near Lake of 
the Woods. 
Fig. 106. (Crabro) Rhopalum pedicellatum Pack. Female. 
PHILANTHIDAE 
Head wider than the thorax; eyes most frequently normal, sometimes slightly 
emarginate within, rarely deeply emarginate within; front wings with three sub- 
marginal cells, intermediate tibiae with two apical spurs; abdomen frequently sessile 
or sub sessile, rarely petiolate, not elongate, first segment frequently with a deep con- 
striction between the first and second. 
Members of this family look something like wasps. The males 
exhibit brushes of long hairs on each side of the clypeus. Honey bees 
are frequently their victims. Philanthus triangularis Fab. according 
to Latreille, digs burrows in hot sandy situations and provisions its 
nest with honey bees. A single bee is sufficient for rearing one 
wasp. Living with the honey bee, which is defenceless against its 
armor, this species stings its unsuspecting host on the under surface 
