464 Mr. Sharp on the ivater-heetles of Japan. 



Volvulus. 

 Volvulus profundus, Shp. 



Amphiops. 

 Amphiops mater, Shji. 



Berosus. 

 Berosus punctipennis, Har. 

 ,, japonicus, Shp. 

 ,, vestitus, Shp. 

 „ lewisius, Shp. 



Hydrochus. 

 Hydrochux japonicus, Shp. 

 ,, (Squalls, Shp. 



Helophorus. 

 Helophorus sp. ? 



,, auriculatus, Shp. 



OCTHEBIUS. 



Octhebius iuermis, Shp. 



Cyclonotum. 

 Cyclonotum latum, Shp. 



,, simplex, Shp. 



HydropMlus orbicularis, F. 

 „ 6/-tfre, Shp. 



Cercyon. 

 Cercijon dux, Shp. 

 ,, «i;<Ms, Shp. 



Cercyon setulosus, Shp. 



„ algarum, Shp. 



,, sharpi, Har. 



,, laminatus, Shp. 



,, aquaticus, Muls. 



,, ovillum, Motsch. 

 Sphceridium quisquilius, L. 



,, unipunctatum, L, 



Cercyon vagus, Shp. 



„ placidus, Shp. 



,, (equalis, Shp. 



,, ustus, Shp. 



,, rotundulus, Shp. 



,, olibrus, Shp. 



,, rubicundus, Shp. 



OOSTERNUII. 



Cercyon sorex, Shp. 



Megasternum. 

 Megasternum gibbulum, Motsch. 

 ,, distinct urn, Shp. 



Pachysternum. 

 Pachysternum hanwrrhoum, Motsch. 



Cryptopleurum. 

 Cryptopleurum subtile. 



Peratogonus. 

 Peratogonus reversus, Shp. 



ADDENDUM. 



Helopliorus a uriculatus. 



Niger, supra fusco-aeueus, palpis pedibusque testaceis ; thorace 

 ad latera auterius siuuato, augulis anterioribus prominiilis ; elytris 

 regulariter seriatim piinctatis, iuterstitiis alternis subelevatis et 

 ultra medium subtuberculatis. Long. 6 mm. 



This is a very distinct species, with a peculiar forma- 

 tion of the sides of the thorax, the front angles being 

 unusually prominent, and the sides a little behind the 

 front somewhat dilated, so that a slight emargination 

 exists behind the front angles ; on the under surface a 

 prominent carina extends longitudinall}' a little distance 

 from the side ; the thorax is covered with fine granu- 

 lations, those near the side being more distinct ; its sulci 

 are fine ; there is a short series of punctures on each 

 side of the suture of the elytra at the base. 



Miyanoshita. 



