51 



In group I. the thorax is transverse /'broader from side to side than from 

 before backwards), not narrowed behind, although four species have the base 

 slightly scalloped out at the sides and prominent in the middle, but in these 

 the posterior angles are blunt. 



In group II. the sides of the thorax are distinctly narrowed behind, and 

 the posterior angles are sharp right angles. 



Ghoup I. 



a. Base of thorax straight. 



B. rufescens* H ead and thorax red ; elytra dark brown with a bluish 

 reflection. Length 2 J lines. 



B. quinquestriatum. Whole of the upper, side dark green. Antennas 

 yellow. Length 2 lines. 



B. obtusum. Whole of the upper side blackish green. Length \\ lines. 

 Of these species rufescens is tolerably common, generally being found in 

 moss on old walls during autumn, winter, and spring; quinquestriatum 

 occurs in similar situations but is scarce; obtusum is perhaps the commonest 

 of the three species, occuring in a variety of situations. 



h. Thorax with the base rather prominent in the middle and more or 

 less strongly scalloped out at the sides. 



Two of these species have a distinct round red spot just before the apex of 

 each elytron, the apex being also sometimes red. These are 



B. biguttatum. Length 2 lines. Colour black with a greenish reflection. 

 Sides of the elytra nearly parallel. 



B. guttula. Length \\ lines. Colour black. Sides of the elytra 

 more rounded. 



The two remaining species of this sub-division are destitute of any distinct 

 round red spot before the apex, though the apex itself is frequently 

 reddish. 



B. aeneum. Length 2 lines. Bronze-black with the legs dark brown. 



B. Manner heimii. Length 1J lines. Brown-black with the legs 

 yellow. All the four species occur on the banks of rivers, but all are more 

 or less local, being abundant when they are once found. 



Group II. 



a. Stria as distinct at the sides and apex as near the suture of elytra* 

 1. S trice on the elytra not punctured. 



