186 Dcscrij)ltons of new Ceylon Coleoptera. [no. 2, new series, 
The femora, the last joint of themaxill. palpi, the mandibles and 
the tarsal joints are dark towards the apex. The last abdominal 
segment of the f. is furnished with a bifid hairy appendage. 
28. Hydrous rufiventr is. N. 
H. ovatus, convexus, supra oleagino-niger, subtus obscure fer- 
rugineus, pedibus dilute piceis, labro seneo, reliquis oris partibus 
cum clypeo testaceis. Long. corp. g. lin. 
Palpi maxill. articulis apicem, versus abruptius incrassatis, art. 
3° quarto sesqui longiore. Antennse art. 7-8 fortiter perfoliatis, 
ultimo acuminato. Caput antice utrinque punctulorum serie subse- 
micirculari et ad oculorum marginem inteliorem impressum. Tho- 
rax punctulorum seriebus 4 lateralibus, 2 subapicalibus obliquis 
abbreviatis signatus. Elytra subtiliter striato punctata. Tarsi 
omnes unguibus basi fortiter unidentatis. Carina prosternalis 
cultriformis. 
Specimen singulum f. nocte ad lumen cepi. 
As far as my resources allow me to ascertain a very anomalous 
species having the perfoliated antennae and toothed claws of a 
Hydrophilus and the cultriform prosternal carina and the elytra 
of a Hydrous. I have placed it in the latter g. on account of the 
sharp edge of the prosternal carina, in which the great distinguish- 
ing character of this g. seems to lie, the same being deeply groov- 
ed in Hydrophilus. 
The insect at once attracts attention by the reddish color of its 
abdomen. It is of a blackish olive color on the back, having how- 
ever the clypeus and the anterior margin of the labrum of a yel- 
lowish brown, the latter being otherwise of a somewhat metallic 
color. The remaining parts of the mouth are more or less yellow- 
ish. Joints 1-6 of the antennae are yellowish too, with the excep- 
tion of the 2nd which is dark, joints 7-9 are blackish and pubes- 
cent. The legs are of a light pitch color. The lower part of the 
head is impressed with two rather semicircular series of punctures, 
similar punctures occurring along the internal margin of the eyes. 
The thorax is marked with six series of them and on the elytra they 
are arranged in lines. The sternal carina is well developed, the 
