440 Mr. David Sharp on the 



HALIPLID^. 

 HaUiilus oralis. 

 Testaceus, vertice, prothoraceque anterius in medio fusco-macu- 

 latis ; elytris seriatim fortiter punctatis, maculis nigris quadratis 

 disjmactis ornatis. Long. 3| — 4^ mm. 

 Var. Testaceus, immaculatus. 



This species is most nearly allied to the European 

 Haliplusfidvus, Fab., but is smaller, the space separating 

 the eyes is rather less, and the serial punctures on the 

 elytra are considerably coarser. The spots on the wing- 

 cases are usually more quadrate and less linear than 

 they are in H.fnlims, but both species vary so much in 

 their markings that little importance can be attached 

 to this. 



Niigata, Tokio, Yokohama, and Kashiwagi. 



Haliplus sharpi. 



Haliplus sharpi, Wehncke, Stett. Ent. Zeit., 1880, 



p. 74. 

 JIakodate ; two examples from a stagnant pool. 



Haliplus japonicus. 



A small series of exponents indicates that the two 

 specimens from which the species was described (Trans. 

 Ent. Soc. Lond., 1873, p. 55) were immature examples 

 of an immaculate variety. The individuals now obtained 

 are spotted in a somewhat indistinct manner, with 

 about ten small quadrate black marks arranged so as to 

 form two angulate transverse series, one on the middle, 

 one behind it ; the head is black. 



DYTISCIDiE. 



Hydrovatus acuminatiis. 



Hydroratus acuminatiis, Motsch., Et. Ent., 1859, p. 42. 



Two examples ; Suruga (near Sazaki) and Otsu. Also 

 in China and Malaya. 



Bidessiis frontalis. 

 Breviter ovalis, convexus, ferrugineus, nitidus, antennis ex- 

 trorsum, abdomine elytrisque fiiscis, Lis ad apicem et ad latera 



