Plate VII. 



Fig. 55. HYDRiENA TESTACEA, Curtis. [F. Elophorida;. G. Hydriena, Kugelann.l 



Head black, minutely and thickly punctate ; antenna: and palpi rufo-testaceons, club of the 

 former fuscous. Thorax pitchy black or brown, with a narrow rufous band on the posterior, and a 

 wider one on the anterior margin, elongate, narrowed behind ; the sides rounded in front, sub- 

 angular a little behind the middle ; coarsely and continently punctate, with an indistinct elongate 

 fovea on each side in front, and a faint impressed transverse line near the anterior and posterior 

 margins. Elytra reddish brown, external margin paler, elongate ovate, rounded at the apex, 

 closely striate-punctate, the punctures large and confluent. Underside dull black. Legs reddish 

 yellow. Length, -J line. 



Widely distributed, amongst aquatic plants in stagnant water, and occasionally beneath stones 

 on the margins of sluggish streams. 



Fig. 56. ELOPHORUS RUGOSUS, Olivier. [F. Elophoridie. G. Elopliorus, F.'] 

 (E. fennicus, Curtis.) 



Pale ferruginous, head and thorax darker. Head short, deflexed, coarsely granulate ; antenna; 

 and palpi rufo-testaceous. Thorax transverse, slightly narrowed in front, sides rounded, posterior 

 angles rectangular, granulate, with four irregular interrupted longitudinal ridges. Elytra tessel- 

 lated with black, a trifle wider at the base than the thorax, slightly dilated posteriorly, each 

 with ten rows of punctures, the alternate interstices forming elevated ridges. Tibiie denticulate 

 externally. Length, 2-2^ lines. 



Found, but not abundantly, throughout Britain. 



Fig. 57. HYDROCHUS ELONGATUS, F., Curtis. [F. Elopboridje. G. Hydroclius, 



Leach. ^ 



Elongate, black with a green or brassy tint. Head thickly and coarsely punctate, forehead 

 with three longitudinal fovere ; antenuie and palpi ferruginous. Thorax elongate, narrowed behind, 

 sides nearly straight, less thickly and a trifle more coarsely punctate than the head, with five fovete, 

 of which the three anterior are disposed transversely a little before the middle, the two posterior, 

 sometimes confluent, close to the posterior margin. Elytra elongate, each with ten rows of large 

 punctures, the 1st (sutural), 3rd, 4th, 5th, 7th, and 9th interstices elevated into ridges, the 1st 

 and 3rd throughout their entire length, the 4th at the apical two-thirds, the others at the basal 

 two-thirds. Legs reddish bro^vn, thighs darker. Length, 2 lines. 



Not rare. 



Fig. 58. ELMIS VOLKMARI, Panz., Curtis. [F. Elmidse. G. Elmis, Latr.'\ 



Elongate, black with a faint brassy tint, slightly shining ; antennre ferruginous, dusky at the 

 tips. Thorax a little longer than broad, narrowed in front, somewhat thickly and finely punctate, 

 with an impressed longitudinal line on each side. Elytra punctate-striate, interstices flat, very 

 finely punctate. Beneath black, apex of abdomen usually pitchy red. Legs reddish brown, tarsi 

 rufous. Length, 1|-1| lines. 



Beneath stones in streams. 



Fig. 59. HYDROPHILUS PICEUS, L. [F. Hydrophilids. G. Hydrophilus, Geoff.-] 

 (Hydrous piceus, Curtis.) 



Elongate ovate, above moderately convex, black, smooth, shining. Head smooth, with an 

 oblicpie sparsely punctate impression on each side between the antennas, and a thickly punctate one 

 near each eye ; antennte and palpi pitchy red, club of the former fuscous. Thorax transverse, 

 narrowed in front, sides rounded. Elytra ovate, each with eight rather faint impunctate longitud- 

 inal strife, interstices flat, the second with a somewhat irregular single row of punctures, the fourth 



13 



