1912.] 231 



are four speciineus in the Champion collection and four in my own. 

 The specimen from Down in the Cambridge University Collection was 

 one of Wollaston's and is a very fine example; Mr. W. E. Sharp has 

 a very nice example taken at Coulsdou, near Caterham, and Com- 

 mander Walker's specimen is also a very fine one. 



9. — 0. paraUeltis, Dej. The species known by this name in our 

 British collections is closely allied to 0. rectangulus, but is a little 

 smaller — 5-7 mm. long — and has a shorter thorax ; the aedeagus has 

 the apical portion considerably broader and shorter. Although it is 

 very difficult to distinguish a large female parallelus from certain 

 small females of rectangulus, yet I believe the two wdll prove to be 

 distinct. The basal margin of the thorax is generally fairly distinct, 

 sufficiently so to prevent large ■parallelus from being mistaken for 

 species of other groups, such as hrevicollis, championi, or rupicoloides. 



This is apparently a rare insect, though there are good series of 

 it in the collections of Mr. Champion and Commander Walker. 

 Localities for it are Deal, Chatham, Sheppey, Eastbourne, Southsea, 

 Sandown and Caterham. The name of the species is very doubtful. 

 Dejean described 0. parallehcs from Spain, and the applicability of his 

 description to the species under consideration is far from complete. 

 Schaum, however, Ins. Deutschl. i p. 580, identified Dejean's descrip- 

 tion with specimens from Austria and Switzerland, and in recent 

 times the species has been treated as a variety of our rectangulus. 

 When it was first discovered in Britain {cf. Proc. Ent. Soc, London, 

 Feb. 1862) no remark svas made as to the grounds on which the 

 sjiecimens w^ere identified with Dejean's species. 



I have reviewed the more critical of the British representatives 

 of this difficult genus, and a few lines is all that need be devoted to 

 the other five species. 



10. — 0. aznreuH,'P?ihv. This is very variable. It is usually brilliantly 

 metallic on the upper surface, Vjut sometimes is nearly or quite black ; 

 and those non- metallic varieties are often confounded with some of 

 the forms I have already discussed. 0. azureus, how^ever, is quite 

 flightless, having the wings very much reduced, while in all the other 

 species they are ample. The sides of the thorax are rounded, without 

 sinuation, and the hind angles are quite obtuse. The aedeagus is but 

 little dissimilar from that of 0. rupicoloides. The vestigial wings vary 

 considerably in size. The obscurely coloured varieties are generally 

 designated as var. dmilis, and may pass as such until a more adequate 

 study of the variation shall be made. 



