648 Mr. Edward Saunders on 
given me the constitution, in a general way, of this 
assemblage in the Palearctic Region. It is as follows :— 
FOSSORES. 
Mutilla : only a few males in an extensive genus. 
Scolia: 9 of one species in a genus of about 20 species. 
Sapyga: ° of one or two species out of 8 or 10. 
Myzine: 2 of one or two species out of 20 or 30. 
Pompilus : both sexes of over 200 described species (pro- 
bably many are synonymous). More than half the genus. 
Salius: many species, but less than half the genus. 
Ceropales: one species out of about 5. 
Pseudagenia : one species out of 4 or 5. 
Astatus: nearly all the species cf a small genus. 
Tachytes and Tachysphex : more than half the species in 
each of these extensive genera. 
Lavra: one species only. 
Gorytes: a small section only of a genus mostly com- 
posed of black and yellow wasp-like species. 
Entomosericus : both species. 
Mimesa : not far from half of about 15 species. 
Sphex: many species of an extensive genus. 
Ammophila: many species of an extensive genus. 
Alyson (small genus): 2 or 3 species. 
Nysson (medium-sized genus): a few species. 
Didineis: both species. 
Dinetus: 1 species only in genus. 
Miscophus: 3 species out of about 10. 
ANTHOPHILA. 
Prosopis: about 5 species out of 60 or 70. 
Halictus: 8 or 10 out of 100 or more. 
Sphecodes*: some 20 species or so. Practically the 
whole genus. 
Andrena: about 20 species out of 200 or more. 
Nomada*: nearly half a large genus. 
Osmia: a very few out of about 200. 
Dioxys *: most of the species (about 6 or 8). 
Phiarus,* Pasites,* Biastes,* Aimmobates * : nearly all the 
species in these small genera. 
The absence of species belonging to the formidable 
Diploptera is remarkable. A brick-red colour is known 
on the basal segment of the abdomen in several species 
* Genera thus marked are known or suspected to be inquiline. 
