1315] 305 



In ac(jijptius the frontal portion of the head is short and strongly 

 rounded, whereas it is much more elongate in hrockmani (cf. fig. 1). 

 The specimen bears on the left side of the head a small third genal 

 spine (cf. tig. 1) which is absent from the right side. The false 

 com!) on the metepimerum contains 14 spines in aegyptius and only 9 

 in hnickniani ; and the hind-coxae are broader in hrockmani than in 

 aegyptius. Otherwise the two species agree very closely. 



The modified abdominal segments of Ch. aegyptmi^ are not well 

 preserved. In hrockmani the seventh sternite almost gradually narrows 

 into a subventral lobe (fig. 2). The stigma of the eighth tergite is large 

 and spinulose. There are four stout bristles below the stigma on this 

 tergite, a row of three or four further down, and a row of four thinner 

 bristles still further veutrally and apically. On the inside is a row of 

 three short bristles aTid an isolated longer apical one. The receptaculum 

 seminis is large, the tail being slightly longer than the head. 



One 9 from Burao, British Somaliland, April 20th, 1915, ofE a 

 bat, collected by Dr. R. E. Drake-Brockman. 



EXPLANATION OF PLATE XXIL 



Fig. 1. — Head of Chiropteropsylla hrockmani, i . 

 Fig. 2. — Posterior abdominal segments. 



Arundel House, 



Kensington Palace Gardens, W. : 

 September, 1915. 



THE BRITISH SPECIES OF SIMULIUM (DIPTERA). 

 BY F. W. EDWARDS, B.A., F.E.S. 



In the Bulletin of Entomological Research for June, 1915, the 

 writer published a somewhat detailed account of the adult stages of 

 the flies of this family to be found in Britain. It has been suggested 

 that this publication may not be available to many British Entom- 

 ologists who are interested in the subject, and on that account the 

 following brief summary of the paper has been prepared. The oppor- 

 tunity is taken of stating that the writer is engaged on further work 

 on the life-histories of these insects, and will be glad to enlist the 

 help of other entomologists in this investigation — particularly in the 

 case of the Scotch species. 



