On Aquatic Carnivorous Coleopiera or Dytiscide. 465 
marginibus anguste ferrugineis, elytris nigro-fuscis, guttis sat numerosis testaceis, 
pedibus rufis, antennis fusco-testaceis, basi testaceo ; elytris crebrius subtiliter sed 
evidenter punctatis ; coxis posterioribus crebrius sat fortiter punctatis ; abdomine 
dense sed subobsolete punctato, fere opaco. Long. 37, lat. 2 m.m. 
This species resembles Hyphydrus pubescens (No. 568) but the elytra have yellow 
spots which almost form a transverse band at the base and in front of the middle, 
and there are other such spots near the apex at the sides, and the ventral segments 
are densely punctured ; the third joint of the front tarsus is quite small. I am 
not able to see any sexual characters. 
Corsica, Sardinia. 409. 
580. Hydroporus decipiens, Sharp, Ann. Soc. Belg. XV, p.113.—-Ovalis, evidenter 
pubescens, sat nitidus, niger, elytris fusco-nigris ad basin signaturis testaceis, pedibus 
rufis, antennis fusco-testaceis, basi testaceo ; elytris crebrius subtiliter sed evidenter 
punctatis ; coxis posterioribus crebrius sat fortiter punctatis; abdomine dense sed 
subobsolete punctato, fere opaco. Long. 4, lat. 24 m.m. 
Closely allied to Hydroporus analis but more elongate and with the colour of 
the upper surface less variegate, the testaceous markings of the elytra being 
limited to their base ; the third joint of the front tarsus is very small; by this the 
species may be distinguished from Dytiscus planus (No. 575) to which it has a 
great similarity ; the dense sculpture of the ventral segments distinguishes it from 
Hyphydrus pubescens (No. 568). I have seen but three individuals, and notice no 
sexual characters. 
Spain, (Guadarrama, Monchique). 410. 
5Si. Hydroporus venator, n. sp.—Ovalis, sat convexus, subtilissime pubescens, 
subopacus, niger, pedibus sordide rufis, antennis fusco-rufis, basi rufo ; elytris 
fuscis, basi indistincte rufescente, omnium dense subtilissime punctatis; coxis 
posterioribus dense subtiliter punctatis; abdomine subtiliter haud dense punctato, 
sub-nitido. Long. 3%, lat. 2 m.m. 
- This species resembles Hyphydrus pubescens (No. 568), but may be distinguished 
at a glance by the extremely fine punctuation of the elytra; in this character it 
resembles Dytiscus marginatus (No. 582), but the smaller size, more obscure 
colour, and less densely punctured undersurface will not allow it to be mistaken 
for a variety of that species: the punctuation on the two basal ventral segments 
at the sides is here comparatively coarse and distinct, while in D. marginatus it is 
obsolete. According to the few specimens before me, the red or yellow marks on 
the basal portions of the wing-cases show a good deal of variation in the extent of 
their development, they consist of twe or three irregular dashes or spots, with a 
