XXI. CRABRO. 149 
gradually narrowing at its base into a petiole, and generally much 
less coloured than in the @, it being most frequently limited to 
an ovate yellow spot on each side of the base of the second and 
third segments, sometimes a few spots at the base of the sixth 
segment, and very rarely the abdomen is entirely black. 
gS @ in most Cabinets. 
+++ This species, the descriptions will show, is extremely 
variable in the colour of its abdomen. I have a single 
specimen in which it is entirely black. It is not un- 
common in the vicinity of London. 
Se. 18. vacasunpus. Panz. 
niger, flavo-maculatus, metathorace levi 2. 
3 femoribus anticis subtis spind obtusd armatis. 
length 45—5} lines. 
Panz. F.G.53.16 ¢. V.d. Lind. pt. 2. 57. 18. 
? Crabro mediatus. Fab. E. S. Sup. 270. 16—17 ; Piez. 312. 20. 
? Blepharipus mediatus. St, Farg. 3. 734.6. g 9. 
Head black, punctured, but not thickly, somewhat shining; 
the vertex having on each side, within the eyes, an oblique 
fossulet, extending in the direction of the posterior stemmata ; 
the stemmata placed in a triangle about its centre, the anterior 
one having in front a longitudinal impression, which extends to 
the verge of the face, where it becomes a smooth and shining 
canalicula, occupying the whole face to the base of the clypeus ; 
the antenne black, with their scape yellow in front; the clypeus 
and interior of the orbits of the eyes, and lower portion of the 
cheeks, covered with a silvery down; the mandibles black, with 
their apex piceous. 
The thorax black, subpubescent ; the dorsolum punctured, 
but not thickly, and slightly shining, having at its base a central 
longitudinal carina, extending to the disk; the scutellum 
also slightly punctured; the metathorax with a longitudinal 
