On Aquatic Carnivorous Coleoptera or Dytiscide. 381 
349. Hyphydrus japonicus, Sharp, Tr. Ent. Soc. Lond. 1873, p. 54.—Ovalis, 
latus, convexus, testaceus, thorace basi, elytrisque fusco-signatis, vertice maculis 
duabus parvis fuscis; elytris stria discoidali ad basin sat distincta, suturali 
subobsoleta. Long. 43, lat. 3 m.m. 
Mas, nitidulus, crebre inzequaliter punctatus, tarsorum quatuor anticorum 
articulo basali posterius valde (preesertim intermediorum) dilatato, abdominis 
segmento basali medio tuberculo crasso subelevato. 
Fem., pedibus paulo magis gracilibus, 
(a.) ut in mare nitidula subtilius punctata ; paulo minor. 
(6.) opaca, obsolete punctata ; evidenter minor. 
In this species the sculpture of the elytra consists of large and small punctures 
mixed together, the large ones are rather numerous and are conspicuously different 
in size from the smaller ones, which are very fine ; the ground colour in this species 
is a peculiar clay yellow, on which the dark markings are displayed in a very con- 
spicuous manner. 
Japan. 40. 
350. Hyphydrus frontalis, n. sp.—Ovalis, latus, convexus, nitidus, confertim, 
fortiter, inzequaliter punctatus, ferrugineus, vertice maculis duabus minutis et 
prothorace basi medio fuscis; elytris testaceis fusco-signatis, stria discoidali ad 
basin sat distincta, suturali subobsoleta. Long. 42, lat. 3 m.m. 
Mas, tarsorum quatuor anticorum articulo basali posterius valde (preesertim 
intermediorum) dilatato, abdominis segmento basali medio vix tuberculato. 
Fem., paulo minor, pedibus paulo magis gracilibus. 
This species is much allied to the H. japonicus, but the ground colour is redder, 
and the punctuation is rather coarser, which is especially to be remarked when the 
fine punctures of the elytra in the two are compared ; the basal segments of the 
hind body are finely punctured on the middle. 
Japan. 41. 
351. Hyphydrus leviventris, n. sp.—Ovalis, latus, convexus, nitidus, sat confertim, 
inequaliter punctatus, punctis majoribus (elytrorum) conspicuis, ferrugineus, 
prothorace basi medio elytrisque fusco-signatis, his stria discoidali ad basin sat 
distincta, suturali fere omnino nulla ; abdomine medio levi, impunctato. 
Mas, tarsorum quatuor anticorum articulo basali sat dilatato ; major. Long. 5, 
lat. 34 m.m. 
Fem., pedibus paulo magis gracilibus, minor. Long. 42 m.m. 
In this species the large punctures of the elytra are strongly developed so as to 
be in conspicuous contrast with the finer ones: though extremely similar to H. 
3D2 
