570 On Aquatic Carnivorous Coleoptera or Dytiscido'. 



humeral portion numerous excessively fine and short scratches, and similar marks 

 may also be perceived on the sides of the prothorax. 



Algeria, Corsica. 826. 



827. Copclatus dimorphus, n. sp. — Oblongo-ovalis, minus jiarallelus et depressus, 

 haud elongatus, nigricans, capite elytrorumque apice jiiceis, pvothoracis lateribus 

 antennis pedibusque rufis; elytris maris seriebus quatuor subtilibus punctorum, 

 femince striis subtilibus circiter decem plus minusve interruj^tis, alternis posterius 

 longe abbreviatis. Long. 4f, lat. 2i m.m. 



The male has the front and middle tarsi a good deal dilated, and the front tibiae 

 thick, short and nearly simple, the thorax with very little sculpture, the el3'tra 

 with about four series of fine elongate punctures. The female has rather numerous 

 fine short strise on the lateral j^ortions of the thorax, and on the elytra very fine 

 striae which have a somewhat interrupted or subpunctate appearance, the first of 

 them is remote from the suture and the alternate ones extend little more than half 

 way to the apex, while the others reach within a short distance of the apex. This 

 species has the prosternal process a good deal raised in the middle and very strongly 

 margined at the sides. 



South America, (Parana). 659. 



Grovp 2. (Nos. 828 to 830). 



Elytra without submarginal stria, but with either three, four or five true strise on 



each wing case. 



Most of the species of this group are known to me only by one or two specimens, 

 they are mostly of elongate parallel form. 



828. Copelatus longicornis, n. sp. — Oblongus, angustulus, subparallelus, nitidus, 

 obsolete punctulatus, rufus, elytris magis castaneis, basi rufo, striis tribus, prima 

 a sutura, tertia a margine laterali, sequaliter remotis. Long. 5, lat. 2} m.m. 



In this species there are three elongate striae on the elytra, the first of which is 

 about as far from the suture as the outer one is from the lateral margin; the male 

 has the front and middle tarsi much dilated ; the front tibiaj rather short and stout, 

 a little bent and distinctly notched below the knee ; the female differs only by the 

 structure of the legs and feet. 



The species is perhaps a variable one, as females from Brazil and Pernambuco, 

 differ from the Santa Rita specimens in size and colour. 



Brazil, (Santa Rita, Sepr., 1860, Salilberg). 655. 



