the British Atomarice. 75 



thorax, — the extreme hinder margin of which, like that of the A. 

 mesomelas, is not raised in the centre, — must serve to distinguish 

 it from its alhes. It would appear to be one of the rarest of the 

 British species, — the only specimen which I have seen, except my 

 own (out of the 1,137 which I have examined), being in the pos- 

 session of Mr. Waterhouse, by whom it was found in the Ham- 

 mersmith marshes during January of 1856. The examples in my 

 own cabinet I captured at Withington, in Gloucestershire, and at 

 Slapton Ley, in the south of Devon. Mr. Haliday, however, in- 

 forms me that it has been met with in Ireland. 



In the Stephensian collection the present species does not exist, 

 Mr. Stephens's A. alra being composed of five specimens of the 

 A. analis (which was his type), and one of the versicolor. 



Sp. 15. Atomaria mesomelas. 

 Dermcstes mesomelas, Hbst, Kaf. iv. p. 143, Tab. 41, fig. 7 



(1792). 

 Cort'icaria dimidiata. Mshm, Ent. Brit. i. p. 112 (1802). 

 Atomaria mesomelas et dimidiata (p.), Steph., Ill, Brit. Ent. iii. 



p. 67(1830), 

 Erich., Nat. der Ins. Deuts. iii. p. 386 



(1848). 

 A beautiful and distinct little Atomaria, readily known by its 

 oblong-ovate form, dark shining surface, and by the bright testa- 

 ceous hue of its limbs and apical half of its elytra, — the junction 

 between the light and dark portions being usually exceedingly 

 abrupt. Its prothorax is occasionally rufescent ; but in normal 

 specimens it is as dark as the basal region of its elytra. It fre- 

 quents marshy and damp places, and is somewhat local. I have 

 taken it in the Cambridgeshire fens, and at Whittlesea Mere, in 

 Huntingdonshire ; at Withington, in Gloucestershire ; at Slapton 

 Ley, in the south of Devon ; and at Tenby, in South Wales. Mr. 

 Waterhouse has captured it in the Hammersmith marshes, at 

 Reigate, and Gravesend ; and Mr. Haliday records it as occurring 

 in Ireland. 



It is an insect so conspicuous and well-marked, that the Ste- 

 phensian specimens standing under mesomelas are unadulterated 

 with any other species. It forms, however, only a portion (though 

 the typical one) of Mr. Stephens's A. dimidiata, — under which 

 name there are two examples of mesomelas (one of which is the 

 Marshamian Corticaria dimidiata), three of analis, and one of 

 a'picalis. 



