DESCRIPTIVE NOTES 319 



the base of the first segment, which bristles with whitish ones. 

 All the segments have a wavy transverse band, wider on the 

 sides than in the middle, and approaching the posterior edge in 

 proportion as the segment is further back. On the fifth 

 segment the yellow band reaches the posterior edge. Anal 

 segment — yellow, black at the base, bristling all over the dorsal 

 surface with papillae of a rusty red, which serve as base to the 

 hairs. A row of like hair-bearing tubercules occupies also the 

 posterior edge of the fifth segment. Below, the abdomen is a 

 brilliant black, with a triangular yellow mark on each side of 

 the four intermediate segments. 



Coxae — black ; thighs yellow in front, black behind ; legs 

 and tarsi — yellow ; wings transparent. 



Male. — The zig-zag mark on the clypeus is narrower, or 

 even absent ; face then entirely yellow ; abdominal bands veiy 

 pale yellow, almost white. The sixth segment has a band like 

 the preceding ones, but shorter and often reduced to two dots. 

 The second segment has underneath it a longitudinal keel, 

 raised and spine-shaped behind. The anal one has below 

 it an angular, rather thick projection. Otherwise like the 

 female. 



This Hymenopteron much resembles Bembex rostrata in 

 size, shape, and arrangement of the black and yellow colouring, 

 but differs markedly in the following characteristics : — The 

 clypeus makes a triangle of three sides, while in other Bembecids 

 it is rounded and convex. Also at the base is a large zig-zag 

 band, formed by two rectangular marks joined together and 

 softened by a silvery down, very brilliant under certain lights. 

 The upper surface of the anal segment bristles with papillae and 

 reddish hairs — likewise the further edge of the fifth segment. 

 The mandibles are only black at the tips, while in Bembex 

 rostrata the base is also black. Their habits are equally un- 

 like ; B. rostrata especially hunts gadflies, while B. julii never 

 catches large Diptera, but takes smaller kinds of very varying size. 

 It is frequent in the sandy land of the Angles, round Avignon, 

 and on the hill of Orange. 



Ammophila julii, H. Fab. 



Length — from 16-22 millimetres. Stalk of abdomen com- 

 posed of the first segment and half the second ; third cubital 



