'UO On Aquatic Carnivorous Coleoptera or Di/tiscidce. 



interstices between the grooves by impressions or divisions, and I have one 

 individual in which this is carried to such an extent that the tenth interstice is 

 represented only by some detached granules, and the ninth is also greatly divided. 



Europe ; Asia Minor, sec. Bedel. (Sweden ; Finland, 60° 50' Sahlberg ; England ; France ; Germany. 

 941. 



992. Dytiscus pisauus, Lap., M.C — Subtus testaceus, metasteruo in medio 

 suturisque plus minusve nigricantibus, supra nigro-olivaceus, prothorace limbo 

 omni elytrorumque lateribus flavo-marginatis, antennis pedibusque testaceis, tarsis 

 posterioribus piceis : prosterui processu sat elongate et acuminate ; coxarum 

 processubus rotundato-obtusis. Long. 30, lat 1 5 m.m. 



Mas, nitidus, elytris versus apicem sat crebre punctatis. 



Fern., subopaca, elytris ad basin paulo ultra medium sulcatis, ad apicem crebre 

 punctatis; prothorace uudique crebre punctato. 



The male has the small palettes on the front feet highly developed, while those 

 on the middle tarsi are much smaller. 



The species is closely allied to D. margin alls, and has exactly the same appear- 

 ance, but it is undoubtedly distinct ; the prosternal process is longer and narrower, 

 the coxal processes are more obtuse, and the furrows on the elytra of the female 

 are rather shorter. The individuals of this species are nearly always somewhat 

 smaller than D. marginalis. 



The extent of the black marks on the undersurface is subject to a good deal of 

 variation : only sulcate females occur, smooth ones being quite unknown. 



Southeni Europe, Corsica, Sardinia, Algeria ; (Southern France, Spain. Italy). 942. 



993. Dytiscus persicus, Wehncke, Stet. Ent. Zeit. 1S76, p. 52. — Augustulus, 

 subtus testaceus, nigro-variegatus ; supra capite thoraceque nigricantibus, hoc limbo 

 omni late flavo-marginato, elytris castaneis, late flavo-marginatis ; prosterni processu 

 sat lato ; coxarum processubus brevibus, obtusis. Long. 29, lat. 14 m.m. 



Mas, latet. 



Fem , nitida, prothorace subtiliter punctulata, intra inarginem impresso ; elytris 

 ad apicem crebre punctatis. 



This species seems to be most allied to D. pisanus, but is narrower and more 

 parallel, and is peculiar in the colour of the wing-cases, which seem also to be of 

 softer texture than usual : as yet the species is known only by smooth females, so 

 that in this respect it differs totally from D. pisanus ; compared with the female of 

 D. pisanus, the punctuation of the thorax is much less, and that on the apical 

 portion of the elytra is less regular and scarcely extends so far forwards : the coxal 

 processes are quite as short as in D. pisanus, and their apices, just a little less 



