Plate VI. — Continued. 



Fig. 51. (JVKLVUS 15IC0L0II, PaijL, Curtis. [F. Gyiinidre. G. Gyrinus, Geoffroy.} 



Narrow, sub-parallel, convex, glo.ssy black vritli a bluish tint. Hcail with two small round 

 iuiprossions between the eyes ; paljn roddisli yellow ; antenn» fuscous. Thorax transverse, nar- 

 rowed and emarginate in front, sides gently rounded, base sinuate. Elytra elongate ovate, each 

 with ten rows of brassy punctures, interstices smooth. Beneath black, reHexed margin of elytra, 

 sides of thorax, apex of abdomen, and legs yellowish red. Length, 8-85 lines. 



Occurs, not uncommonly, near the coast, in salt marshes, and ditches of brackish water. 



Fig. 52. ACILIUS CANALICULATUS, Nicolai, ? . [F. Dytiscidse. G. Acilius, Leach.] 

 (A. caliginosus, Curtis.) 



Ovate, depressed. Head pitchy black, parts of the mouth, antenna;, and an arcuate patch 

 between the eyes reddish yellow, finely reticulate and sparsely minutely punctate. Thorax pitchy 

 black, margins, and a central transverse band dilated posteriorly at each end, and sometimes 

 interrupted in the middle, reddish yellow; transverse, narrowed and emarginate in front, sides 

 slightly rounded, base sinuate, posterior angles acute; finely reticulate and distinctly punctate, the 

 punctures si)arse in front and in the middle, closely set at the sides. Scutellum black, finely 

 reticulate. Elytra reddish yellow, covered, save along the suture and at the sides, with innumerable 

 small confluent black spots, broad ovate, dilated at the sides behind the middle, minutely punctate, 

 each with three indistinct longitudinal ridges. Underside and legs reildish yellow, meso- and 

 meta-thorax and base of abdominal segments frequently pitchy black. Length, G-7 lines. 



The female has the thorax depressed, especially at the sides posteriorly, and the elytra have 

 each four wide longitudinal channels clothed with long yellowish red pubescence. 



Found in the Fens of Huntingdonshire and Lincolnshire ; in the north of England ; and in 

 Scotland. 



Fig. 53. CYBISTER ROESELII, Fab., Curlit:, $ . [F. Dytiscida>. G. Cybister, Curtis.'] 



Ovate, dilated behind, depressed. Head olive-green, shining, very minutely and sparsely 

 punctate, labrum, epistome, palpi, and antennaa pale yellow. Thorax olive-green, lateral margins 

 broadly, centre of the anterior and imsterior margins very narrowlj-, yellow; transverse, narrowed 

 and emarginate in front, sides slightly rounded, base sinuate, posterior angles acute, with an ex- 

 ceedingly fine and sparse punetatimi, and a few large punctures at the sides and along the anterior 

 margin. Elytra ovate, brownish olive-green, with a broad pale yellow sub-marginal band, and a 

 narrow oblique stripe at the apex, each with three rows of punctures. Underside and legs reddish 

 yellow. liength, 12-1.") lines. 



The female difl'ers from the male in having the thorax covered with deeply impressed curved 

 lines, and the elytra furnished to within about a fifth of their length from the apex with closely 

 set waved longitudinal striga;. 



The only example hitherto detected in Britain "was found the 30th September, 1S26, in a 

 puddle at Walton, Essex." 



Fig. 54. FAUNUS FROLEFERICORNIS, Fab. [F. ParnidEc. G. Paraus, Fab.] (P. 

 iinprcssus, Curtis.) 



Fnscous, clothed with a dense short yellowish-grey pubescence, elongate, sub-cylindrical, finely 

 and rather thickly punctate. Head depressed in front ; antenna- approximate, black, the club 

 reddish yellow. Thorax a little narrower than the elytra, narrowed in front, with a sliglitly curved 

 impressed line on each side, and occasionally two fovea' near the base. Elytra with foeMe traces of 

 etrise. Length, 2^-2^ lines. 



Common on the muddy margins of ponds and ditches. 

 12 



