80 SPHECIDA. 
+4+ Jurine having observed some Spheces and Pompilé 
with the third submarginal cell petiolated, established this 
genus for their reception, and it is from this character that 
the name is derived, viz. picxos, from picxos—a stalk. He 
divided it into two families, the first to receive the former 
and the second the latter. Experience has proved that the 
last will not stand, as they are merely accidental varieties of 
the neuration of the wing in Pompilus (see obs. under P. 
niger and viaiicus); but the former I retain, for all that I 
have examined are specifically distinct from the Ammophila 
with two joints to the petiole, and the petiole of the third 
submarginal cell always accompanies those peculiar specific 
differences. St. Fargeau has made it the third subdivision 
of the second division of Ammophila, in the tenth volume 
of the Encyclopédie Méthodique, which is the more sur- 
prising, as in dividing Gorytes and Crabro he almost splits 
hairs; but I here restore the genus, and shall consider it a 
good one, until I find individuals of the same species with 
the nervures of Ammophila sabulosa, which I have never 
yet discovered, although I have examined many both British 
and continental specimens. 
Spr. 1. campestris. Lat. 
niger, metathorace in medio depresso et a latere oblique striato, 
abdominis segmento secundo et tertio rufo. 
length 7—8}3 lines. 
V. d. Lind. pt. 1. 92. 
Ammophila campestris. Latr. Gen. 4. 54; Nouv. Dict. 1. 450; St. 
Fargeau, Ency. Méth. 10. 453. 
Black, pubescent, punctured: head with a central impressed 
line in front of the anterior stemma extending to the face; 
stemmata placed upon the vertex. 
The thorax having the dorsolum very delicately transversely 
