432 ~ On Aquatic Carnivorous Coleoptera or Dytiscide. 
In the male the thorax is broader at the base than it is in the female, the 
front and middle tarsi are broader than in the other sex, and the claws of the 
anterior ones are much more developed, the inner one being also rather longer than 
the outer one. 
Southern Europe. (Spain, Guadarrama, Reynosa). 308. 
485. Hydroporus martini, Fairm., M.C.—Oblongo-ovalis, angustulus, omnium 
brevissime subtilissimeque pubescens, subopacus; subtus niger, supra minus dis- 
crete coloratus, elytris fusco-ferrugineis, basi pallido, prothorace seepe ferrugineo 
lateribus dilutioribus, capite, antennis pedibusque testaceis ; elytris apicem versus 
muticis vix sinuatis; corpore dense subtilissime punctato, prothorace basi punctis 
majoribus conspicuis. Long. 45, lat. 2; m.m. 
The male has the front and middle tarsi broad, and the claws of the front ones a 
good deal more developed than in the female. 
I have a variety of the male in which the thorax is a good deal broader than 
usual. 
I have no doubt this supposed species will prove to be a mere variation of H. 
sardus, (H. offinis, Aubé), from which it differs only in colour; the dark marks 
of the upper surface cover a larger portion of the surface, and instead of being 
black are of a ferruginous colour. 
Corsica. 247. 
486. Hydroporus sardus, Har., M.C.—Oblongo-ovalis, omnium  subtilissime 
brevissimeque pubescens, subtus niger, supra testaceus, prothorace parte basali 
elytrisque signaturis magnis confluentibus, nigricantibus; elytris apice sinuato ; 
prothorace elytris angustiore, lateribus plus minusve curvatis, angulis posterioribus 
obtusis haud rotundatis; corpore dense subtilissime punctulato, prothorace basin 
versus punctis majoribus sat conspicuis. Long. 42, lat. 22 m.m. 
The male has the front and middle tarsi broad, and the claws of the front ones 
much more developed than in the female, and the sinuosity at the apex of the 
elytra is not quite so strong, and the thorax is usually broader. 
The species is a very variable one in colour, and in some other respects; the 
black marks on the elytra sometimes extend to within a short distance of the base, 
and in such individuals are less confluent than they are in others where the black 
marks are widely absent on the basal part of the elytra, but form a very broad 
irrecular fascia across the middle. Large specimens of the male sex, are broader 
and have the sides of the thorax more rounded than in other individuals. In this 
species, as well as in the following one, the apex of the scutellum is very distinctly 
- exposed. 
Sardinia. (Chilivani 5, 1879, and Czieri 10. 10. 1879, Damry). 251. 
