242 IIYDROPHILIDiE. [Hyh'ocJnif. ■ 



Harborongh (Rev. A. Mattliews) ; Nortliumberland, Gosforth (Mr. Bold); Soot- 

 land, very local, Lowlands, Tweed, Forth, Tay, and Clyde districts (Perth, Dumfries, 

 &c.). 



B. elong-atus, Schall. Elongate, head and thorax metallic black or 

 green, coarsely punctured, the latter plainly longer than broad, with five 

 distinct depressions arranged in two transverse rows, the anterior con- 

 taining three and the posterior two ; elytra black or brownish with 

 strongly punctured, crenate stride, alternate interstices raised in ridges, 

 third and fifth eff"aced behind ; underside silky black i legs pitchy : tliis 

 is the largest of our species. L. 3|-4| mm. 



Widely distributed throughout England, although somewhat local ; apparently 

 commoner in the Midlands and south than in the north ; Scotland, rare, Lowlands, 

 Forth district only. 



Occasionally this species has the upper surface entirely metallic green 

 or bronze. 



H. carinatus, Germ. Very like the preceding, but considerably 

 smaller and narrower ; the depressions on the thorax are shallower, and 

 may be reckoned as .seven in number instead of five, as two are rather 

 indistinctly traceable near the posterior angles ; the tliird and fifth inter- 

 stices of the elytra, also, are not efi^aced behind as in H. elongatws. 

 L. 21-2^ mm. 



A fen species ; very local; first taken in 1859 in Holme Fen, Huntingdonshire, by 

 Mr. Dossetor, and since then in Wicken Fen, Cambridgeshire, and other localities 

 near Cambridge. 



K. ang"ustatus, Germ. Elongate ; upper side usually metallic 

 green or bronze, but sometimes the elytra are brown or violet, or the whole 

 body is of a metallic violet colour or almost black ; head and thorax 

 strongly punctured, the latter with five or seven depressions, the two 

 outside ones in the posterior row being often obliterated ; elytra with 

 strongly punctured, crenate strife, with none of the interstices raised in 

 ridges ; this character will at once separate this species from the otlier 

 three ; underside silky black ; legs reddish, knees and extremities of 

 joints of tarsi usually dark, L. 2-3| mm. 



Common and widely distributed in the Midlands and south of England, but 

 apparently less common further north : it is not recorded by Mr. Bold from North- 

 umberland and Durham, and in Scotland is rare in the Tweed, Forth, and Clyde 

 districts. 



HENICOCBRUS, Stephens. 



This genus comprises three species, all European, of which we possess 

 one as British ; they are found, in running streams under stones, and 

 occur chiefly in mountamous or hilly districts : the shape of the j)alpi 

 and the difference of the sculpture of the thorax in the sexes serve to 

 mark the genus. 



The transformations of JTeMicoeenw eocseulpius are described by Wailes (Eat. Mao-. 

 1833, p. 25G) and Westwood (Classification, i. 121) : the species arc fouiul in the 

 crevices of stones in rivulets, just level with or a little above the suriace; the larva? 



