376 CLAviCuHNiA. \_Elmls. 



much larger number will be discovered ; six species occur in Britain, 

 ■which may be distinguished as follows : — 



1. Thorax impressed ut base, with a lateral line 

 on each side parallel to margin, reaching frona 



base to apex (Eliuis, i. sp.) E. ^njkus, Mull. 



II. Thorax not impressed at base. 



i. Thorax witli a lateral line on each side 

 parallel to margin. 



1. Length 3 mm.; elytra behind middle 

 wider than thorax ; lateral lines of thorax 

 somewhat converging in front {Latelmis, 



Reitter) K. VoLKiiAHi, Panz. 



2. L. 1 mm. ; elytra and thorax forming a 

 parallel-sided oMong ; lateral lines of 



thorax parallel (Esolu-^, Muls.) . . . . E. PAEALLELOPiPEDUfi, iliill. 

 ii. Thorax wilhout laterallines. 



1. Thorax finely punctured bnt not rugose ; 

 elytra with second and fourth interf-ticos 

 slightly n.ised ; anteunse, as a rule, darker, 



at least at apex. {Riolns, Muls.) 



A. Length 2 mm. ; elytra longer in pro- 

 portion to thorax ; colour darker . . E. subviolacetjs, M«7/. 



B. Length l-g-li nim. ; elytra shorter in 



proportion to thorax ; colnir lighter . E. CirPREUS, iflnll. 



2. Thorax finely rutrose ; elytra with second 

 and fourth interstices quite even ; antennae 



red, not darker at apex E. nitens, Miill. 



E. eeneus, Miill. Black, moderately shining, with the elytra of a 

 dark bronze metallic colour, clothed with very short and fine greyish 

 pubescence ; head exceedingly finely punctured j antennse brown with 

 base red ; thorax narrower than elytra, as long as broad, gradually a little 

 narrowed in front, upper surface divided into three portions by lateral 

 lines on each side of disc parallel to sides, and with a transverse im- 

 pression at base ; elytra convex, shar])ly narrowed behind, with strongly 

 punctured strise, fourth and sixth interstices somewhat raised ; legs pitchy- 

 brown, tarsi reddish. L. 2 mm. 



In running water, clinging to stones, &c. ; somewhat local, but by no means 

 uncommon; generally distributed in the Loudon disirict and the South; not so 

 coaimon perhaps in the Midlands, but widely distributed ; Yorkshire ; Manchester 

 and Northumberland districts; Scotland, Solway, Tweed, Torth, and Moray districts, 

 and probably general ; it is most likely as common in Ireland. 



E. Volkinari, Panz. (Latelmis Volkmari, Reitter). By far the 

 largest and broadest of our species, and easily recognized by its size ; 

 oblong, black, with a very slight, often almost imperceptible bronze 

 reflection ; head finely rugose, antennae of a bright reddish colour at 

 base, darker towards apex ; thorax about as long as broad, finely punc- 

 tured, slightly narrowed in front, with the engraved lateral lines slightly 

 converging towards apex, and with no impression at base ; elytra rather 

 long, rather broader at base than thorax, some^vhat widened behind 



