RHYMENOPTERA. ^ 419 



den pubescence ; the middle of the mandibles and the scape 

 yeilow. Thorax : a spot on each side of the collar, the tubercles, 

 and a spot in the middle of the post-scutellum, yellow; the 

 mesothorax longitudinally roughened ; the scutellum shining 

 and with longitudinal punctures; the metathorax with a deep 

 central longitudinal channel, which is transversely striated ; the 

 base of the metathorax coarsely obliquely striated, posteriorly 

 transversely so ; the wings slightly coloured, the nervures rufo- 

 testaceous ; the tibiae and tarsi yellow ; the claw -joint fuscous, 

 as well as the second, third and fourth joints of the posterior 

 pair. Abdomen smooth and shining, the second, third and fourth 

 segments with a yellow fascia on their basal margins, the first 

 three interrupted ; the apical segment pinched at the sides and 

 covered with yellow pubescence ; beneath, immaculate. 



The male closely resembles the female, but has a silver}- pu- 

 bescence on the clypeus, and the spots on the collar and post- 

 scutellum obliterated; the fasciae on the abdomen reduced to 

 oblong lateral spots; the tibiae have a black stain beneath. 



Hab. Hudson's Bay. (Coll. G. Barnston, Esq.) 



135. CRABRO TRIFASCIATUS. B.M, 



Crabro trifasciatus, Soy, Narr. Exped. St. Peter's River, Append. 

 p. 7-1. 4 (var. 6-maculatus?). 



Hab. Pennsylvania ; Hudson's Bay. 



This species scarcely differs from C. vagus, and may be re- 

 garded as the American representative of it : the yellow markings 

 are much paler ; the antennae of the male are of the same form 

 as in C. ragus, and are apparently 12-jointed, as in that species. 



136. CRABRO FRIGIDUS. B.M. 



Female. Length 5 lines. Black : the head finely punctured, 

 the cheeks sparingly so, smooth and shining; the ocelli in a 

 curve on the vertex ; the scape and mandibles yellow, the base 

 and apex of the latter black. Thorax : the mesothorax longitu- 

 dinally striated ; the scutellum shining, punctured at the base, 

 and longitudinally striated beyond ; the metathorax with a sub- 

 defined half-circular space at its base, which is coarsely striated 

 obliquely ; posteriorly it is very coarsely and deeply rugulose ; a 

 spot on each side of the collar and the tubercles yellow, the an- 

 terior lateral angles of the collar subdentate ; the knees, tibiae 

 and tarsi yellow, the apical joints of the latter fuscous, the ex- 

 treme apex of the tibiae with a ferruginous stain; the wings 



