326 On Aquatic Carnworous Coleoptera or Dytiscide. 
191. Hydrovatus acuminatus, Motsch., M.C.—Brevis, sat latus, parce subtiliterque 
punctatus, testaceo-ferrugineus, supra magis castaneus, antennis tenuibus, simpli- 
cious. Long. 2, lat. vix. 13 m.m. 
Very closely allied to Hydrovatus clypealis (No. 179), but smaller and narrower, 
and with the front and middle tibie, only about half as broad, the antennze more 
slender but scarcely longer, the hind coxze are also a little broader. 
If, as I suppose, I have both sexes before me, these only differ by the male being 
slightly more shining than the female. 
China, (Kiu Kiang, Lewis), Formosa, Celebes, Lombock, Sumatra. 6. 
192. Hydrovatus fulvescens, Motsch., M.C.—Oblongo-ovalis, brevis, sat latus, 
valde nitidulus, castaneo-testaceus, sparsim subtiliter punctatus, antennis brevibus 
simplicibus ; coxis posterioribus sat fortiter sed sparsim subineequaliter punctatis. 
Long. 1%, lat. 1s m.m. 
A very smail species, distinguished by its very shining surface, and sparse fine 
punctuation: the front tibiee are comparatively slender. I have seen only two 
individuals, which have the antennz short, the penultimate joints being not so long 
as broad ; the species is most allied to Hydrovatus acuminatus, but is considerably 
smaller, narrower, and Jess convex in form, more shining and more sparsely punc- 
tured. 
East India, sent by Wehncke. 450. 
193. Hydrovatus fusculus, n. sp.—Brevis, sat latus, nitidus, confertim sat fortiter 
punctatus, castaneus, antennis tenuibus simplicibus; coxis posterioribus fortiter 
crebre punctatis. Long. 2%, lat. 13 m.m. 
This species is rather smaller and narrower than Hyphydrus cuspidatus (No. 180), 
and is of more obscure and uniform colour; it has the front tibiz: much thinner, 
and the antenne rather more slender. The sexual differences appear to be ex- 
tremely slight. 
Macassar, Jan., 1874, (Beccari), Formosa, China. Though the specimens from these different localities 
differ slightly, I cannot notice anything to distinguish them as species. 7. 
194. Hydrovatus fasciatus (Wehncke), n. sp.—Brevis, sat latus, nitidus, confertim 
minus fortiter punctatus, ferrugineus, prothorace (lateribus exceptis), elytrisque 
piceo-castaneis ; antennis tenuibus simplicibus ; coxis posterioribus fortiter crebre 
punctatis. Long. 23, lat. 13 m.m. 
Extremely similar to Hydrovatus fusculus, but slightly larger and more elongate, 
a little different in colour, and with the elytra more finely punctured. 
Australia, (Brisbane, Rockhampton). 446. 
