95 . 
HYDATICUS CINEREUS. 
Order Coleoptera. Fam. Dyticidse Leach . Hydrocan- 
thari Lat. 
Type of the Genus Dytiscus transversalis Fab. 
Hydaticus Leach , Sam. Dytiscus Linn., Fab., Oliv., Lat., Gyl., fye. 
Antennae inserted close to the eyes at the base of the mandibles 
filiform, 11 -jointed, 2nd joint not much shorter than the 3rd, 
4th longer than the 3rd, the remainder nearly of equal length, 
somewhat clavate, excepting the terminal joint which is slightly 
curved and somewhat conical (fig. 6). 
Labrum naked transverse, slightly emarginate (1). 
Mandibles small, bent, broad and bifid at their extremity (2). 
Maxillae small, bent, very acute, ciliated internally. Palpi , in- 
ternal slender, 2-jointed, 2nd joint the longer, curved j external 
4-jointed, 1st joint minute, 2nd and 3rd slightly clavate, trun- 
cate, 4th large, slightly attenuated at the apex and truncated (3). 
Mentum transverse, lobed on the sides and slightly produced in 
the middle. Palpi 3-jointed, attached to a cylindric scape, 1st 
joint short, 2nd and 3rd long, the latter somewhat conical. La- 
bium large, rounded, ciliated (4). 
Head rounded. Thorax transverse broad. Elytra convex ovate , smooth 
in both sexes. Wings 2. Scutellum distinct. Tibiae all short. 
Tarsi 5 -jointed, anterior patelliform and ciliated in the males (5) ,* 
the middle pair with the 3 first j oints dilated with suckers beneath (5*). 
Claws simple, of equal length. Posterior tarsi compressed, elongated, 
ciliated on both sides with very long fine hdirs. Claws slightly 
hooked, one longer than the other. 
Cinereus Linn. Faun. Suec. p. 215. n. 771. Gyll. Ins. Suec. v. 1. 
p. 474. n. 8. not of Fab. Ent. Syst., nor of Mars. Ent. Brit. 
Blackish, smooth, shining. Head ochraceous, black at the base 
with 2 oblique black lines between the eyes united behind. 
Thorax black, with an aureous ochraceous fascia across the 
middle uniting with the lateral margins of the same colour. Scu- 
tellum black. Elytra black, speckled with pellucid yellow, and 
a narrow line of the same colour down each side of the suture ; 
external margin dull ochraceous : beneath ochraceous, ferrugi- 
nous towards the apex. Antennas and legs ochraceous, the former 
fuscous towards their extremity, the latter with the tibiae and the 
tarsi of the 4 posterior chesnut-colour. 
In the Cabinets of Mr. Chant and Mr. Bentley. 
