250 HYDRorHiLiDiE. [Hydrce?ia. 



Hack; thorax black or brown with margins more or less broadly tes- 

 taceous, more closely punctured at sides than on disc, sides obtusely angled 

 just behind middle in female, more rounded as a rule in male, rather 

 strongly contracted to base ; elytra castaneous brown, oblong, with sides' 

 moderately rounded, apex obliquely truncate, with six rows of strong 

 rather square punctures on each between the suture and humeral angle ; 

 male with the last joint of the maxillary palpi thickened and excised on 

 its innfer margin towards apex, so that the apex is pointed ; legs testa- 

 ceous. L. 1-H ^^• 



Local ; a nortberu species ; usually found in running water attached to stones ; 

 Knovvle, near Birmingham; Derbyshire; Scalby Beck, Yorkshire; Lancaster (River 

 Lune) ; Northumberland district (The Wansbeck, Wallington, &c.) ; Scotland, rare, 

 Lowlands, Tweed, Forth, and Solway districts. 



K- pygrmsea, Wat. {Sieholdi, Kosh.). Eather short and broad, de- 

 pressed, shining castaneous brown, disc of thorax usually more or less 

 darker ; head black or dark brown ; thorax cordiform, rather wide in 

 front, strongly and sinuously contracted to base, coarsely and diffusely 

 punctured, especially on disc ; elytra short and broad, more so in female 

 than in male, \\dth six rows of rather large but not deep punctures on 

 each between suture and humeral angle, which are somewhat irregular, 

 and behind the middle are hardly traceable ; apex rounded ; male with 

 the femora a little thickened, and the posterior tibice strongly thickened 

 inside from about middle to base ; female with the surface of the elytra 

 somewhat depressed behind middle, so that the suture appears somewhat 

 raised ; legs reddish testaceous. L. H-lf mm. 



Rare ; Scarborough ; Northuraberland district (The Wansbeck, &c.) ; Scotland, rare. 

 Lowlands, Solway district only. 



K. pulchella, Germ. A small species, rather elongate and de- 

 pressed, brownish or yellowish testaceous with the head black and the 

 disc of thorax more or .less dusky ; palpi clear yellow ; thorax broader 

 than long in the middle where the sides are angled and thence contracted 

 to base, rather strongly and moderately closely punctured ; elytra oblong- 

 oval, with six rows of rather feeble punctures on each between suture 

 and humeral angle, punctuation confused towards sides and behind middle, 

 but usually more or less regular on disc ; apex rounded ; legs clear 

 yellow-testaceous. L. 1-1 ^ mm. 



Rare; in running water ; River Dove, near Burtou-ou-Trent ; Derbyshire; Scalby 

 Beck, Yorkshire ; Stretford, near Manchester ; Northumberland district ; Scotland, 

 rare, Lowlands, Forth, Tay, and Solway districts. 



These three species appear to present some difficulty, probably because 

 the latter two are so rare that other species are mistaken for them : H. 

 atriccqnlla may at once be distinguished by the truncate apex of its 

 elytra, very strong and regular punctuation^ and the thickened joint of 

 the maxillary palpi in male ; H. pijrimcea by its thick broad elytra, more 

 or less confused punctuation, and the thickened tibite of male ; //. pul- 

 diclla by its feeble and irregular punctuation, small size, and lighter 



