1885. 



77 



ii. Prevailing colour pitchy or blackish ; base and apex of elytra to a greater 

 or less extent light. 

 1. Last segment of abdomen in both sexes with a plain impression, termi- 

 nated on each side by a small prominence. 

 R. nitidulus, Fabr.— Rather elongate, slightly convex ; head large, especially in 

 the male ; eyes prominent ; thorax considerably longer than broad, more so in the 

 male than in the female, plainly punctured on disc, finely punctured on sides ; elytra 

 with extreme side margins, apex and basal fourth part light red, with rather strongly 

 punctured stri^. Length, U— 2^ lin. 



Eare ; under bark and at sap ; Eannocli, Sherwood Forest, Dr. 

 Power ; Raunoch, Mr. Champion. 



The only real distinguishing mark for this species is the impression 

 on the last abdominal segment, which never varies ; large specimens 

 of B. dispar do duty for it in many collections : as a rule it is larger 

 than that species, and there are certain differences in colour, but 

 neither colour nor size are really reliable characters. 



2. Last segment of the abdomen simple. 



E. dispar, ayll.- Elongate, slightly flatter than the preceding species ; head 



large, especially in the male ; eyes prominent ; thorax evidently longer than broad, 



more so in the male than in the female, sides slightly rounded, finely punctured at 



sides, more plainly on disc; elytra plainly punctate-striate, apex broadly and 



shoulders narrowly light red, the colour, however, badly defined and variable 



•^ ^ Length,!^ — 2 1m. 



Not uncommon at sappy bark in the North of England, Scotland, 

 and Ireland. Newcastle, Braemar, Aviemore, Eannoch, Co. Down, 

 Mr. Champion ; under bark of pines and in fungus growing on de- 

 cayed trees, Chat Moss, Dunham, &c., Mr. Chappell ; under poplar 

 bark, Stretford, Mr. Eeston ; Eannoch, and in profusion at Balmuto 

 (Fife), Dr. Power. 



iii. Elytra black or brownish-black, with a plainly defined yellow spot on each 



a little before apex. 

 R. Upustnlatus, Fabr.-Eather flat, shining; thorax not mueh longer than 

 broad, with sides and anterior and posterior angles slightly rounded, thickly and rather 

 finely punctured; elytra with plainly punctured striffi, with a very badly defined 

 yellowish spot at the shoulder, and a plain one before apex. Length, l—H Im. 

 Under bark ; the commonest species of the genus. 

 This species varies very much in colour, some specimens being 

 piceous, and others light testaceous ; the former are easily distinguished, 

 as the two spots on the elytra are always plain, if the ground colour 

 is at all darker ; pale examples, however, may be confused with B. 

 perforatus, which is about the same size, but the rounded sides ot the 

 thorax, and much more plainly punctured stri^ of the elytra, will dis- 

 tinguish them. 



