BY THOMAS G. SLOANE. 203 



the following are characters that distinguish it : — Size smaller; 

 elytra wholly of a bright metallic violet colour; prothorax with 

 three (not two) marginal punctures; elytra more depressed, more 

 rounded on the sides and more narrowed to the base, with the 

 humeral angles less erect. 



Before describing the new species to be added to the group of 

 which Carenum niarginatiim, Boisd., is the type, it has seemed 

 •adA'isable to review the described species of the group as well as 

 the present state of my knowledge will allow. It should be 

 noted that in some species of this group, and in other allied 

 species, there is a considerable difference between different speci- 

 mens in the appearance of the dorsal surface of the elytra; some 

 specimens have the suture lightly impressed and not placed in a 

 channel, so that the elytra are not separately convex, while in 

 other specimens the suture forms a deep channel and each elytron 

 is separately convex. I had thought this was a sexual di£ference 

 and that the deeply impressed suture was a character of the male, 

 but though, generally speaking, this seems to be the case, it does 

 not appear, from the evidence on the subject I have been able to 

 obtain, to be an invariable rule; it is a subject requiring further 

 investigation. 



Four species formerly attributed to the war^maiwrn-group 

 should certainly be removed from it, viz. : — C. striato-punctatitm, 

 Macl., C. pfanipenne, MacL, C. subplaiiatum, Bates, and C. bated. 

 Masters. This leaves twenty species in the group which may be 

 divided into two sections according as their colour tints are green 

 or blue; the species of each section are arranged below in the 

 order of their priority. 



Section I. — Species the colour tints of which are green. 



C. marginatitm, Boisd. C. viridi-marginationi, Macl. 



C. laterale, Macl. C. terrcn-regince, Macl. 



C. sahcostatum, Macl. C. imitator, SI. 



