of DytiscidcB Darwiniance. 13 



After a careful examination of several species, I must agree with 

 Stephens in considering that there is only one claw, and that 

 moveable, the apparent upper claw being only a long seta. 



Hydroporus, Clairv. 

 A. Thoracis lateribus rotiindatis, elytrorum apice dentato. 



1. (17.) H. Darwinii, Bab. 

 Oblongo-ovatus, subdepressus, punctatus, ferruginens, vertice 

 nigro, thorace raaculis 2 fuscis lineisque 2 abbreviatis im- 

 pressis, elytris nigris margine externo maculis 2 lateralibus 

 lineisque interruptis flavis, corpore subtus pedibusque fer- 

 rugineis. (L. c. 2 ; lat. 1 lin.) 

 Oblong-ovate, depressed, thickly punctured throughout. Head 

 rounded, pale testaceous, narrowly black behind. Antennse tes- 

 taceous, with the terminal joints ringed with black. Tliorax pale 

 testaceous, short, transverse, broadly and deeply emarginate in 

 front, the angles acute, the sides straight and parallel, except near 

 to the anterior angles, where they are strongly rounded, posterior 

 margin nearly straight, produced in the middle, narrowly mar- 

 gined with fuscous, and two small spots of that colour connected 

 with it towards its middle ; also an abbreviated longitudinal im- 

 pressed line on each side. Elytra broader than the thorax, ovate, 

 the apex acute, with a minute tooth upon each side, black ; the 

 anterior margin, two angular marginal spots, a line interrupted 

 in the middle next the suture, and about four very slender and 

 much interrupted lines upon each, testaceous. Body beneath 

 testaceous, the abdomen rather darker. Legs testaceous, the 

 posterior pair darker. 



Hab. King George's Sound, Australia. 



2. (18.) H. undecimlineatus, Bab. 



Oblongo-ovatus, subdepressus, punctatus, flavus, elytris sutura 



lineis 5 maculisque 2 lateralibus nigris, corpore subtus anten- 



nis pedibusque flavis. (L. c. 2 ; lat. 1 lin.) 



Oblong-ovale, depressed, thickly punctured throughout. Head 



and thorax as in the last, except that the latter has two faint dark 



clouds upon its hinder margin alone, and the sides are uniformly 



rounded. Elytra broader than the thorax, ovate, the apex acute, 



with a minute tooth upon each side, yellow ; with the suture, five 



regular lines upon each, two oblong spots between the first and 



second, and two spots (one angular, and at about the middle, the 



