On Aquatic Carnivorous Coleoptera or Dytiscide. 325 
189. Hydrovatus caraibus, n. sp.—Brevior, convexus, nitidus, ferrugineus, 
elytris pectoreque fuscis, illis basi crebre fortiter, versus apicem obsolete 
parcissime punctatis. Long. 23, lat. 1$ m.m. 
This species is convex, and not very broad; the front of the head is very dis- 
tinctly margined, the surface of the head impunctate. The thorax is at the base 
closely and rather coarsely punctured, elsewhere the punctures are indistinct. The 
elytra at the base are deeply and closely punctured, but the punctures become finer 
and more scanty behind so as to be altogether wanting at the apex ; they are dark 
in colour, without spots, but the apex is pale. The hind coxe are coarsely punc- 
tured. 
The individual described is no doubt a female as it has the tarsi quite small ; the 
wing-cases are, however, shining. It is larger than H. brevipes (No. 187), and 
distinguished from it by the closer punctuation of the base of the wing-cases, which 
also in the female of H. brevipes are dull. 
Guadaloupe. 1177. 
190. Hydrovatus aristidis, Lep. Ann. Soe. Fr., 1879, p. [xxxii.-—Crebre punctatus, 
brevissimus, ferrugineus, elytris thoraceque infuscatis, hoc medio late rufo, illis 
obscure rufo-signatis ; prosterno medio transverso. Long. 23, lat. 12 m.m. 
Mas, antennis deformibus, articulis intermediis dilatatis, 8-10 simplicibus, 11° 
iterum dilatato. 
Extremely similar at first sight to Hyphydrus cuspidatus (No. 180), but with 
the punctuation of the upper surface rather closer and coarser; the clypeus is 
margined, but the margin in the middle is more depressed than in H. cuspidatus, 
and therefore not so distinct. The front and middle tarsi are a good deal longer 
than in H. cuspidatus, and the process of the prosternum is transverse instead of 
triangular, the front part being truncate instead of acuminate: the punctuation of 
the coxze is less close and rather coarser. 
I have only seen a single specimen of this species, which I have no doubt is a 
male : the structure of its antenne is very remarkable : the first and second joints 
are simple, the third is broader than second, the fourth is broader than the third, 
very short, and slightly produced on the inner side, the fifth is extremely short and 
very broad, being much produced on the inner side, the sixth is very transverse, 
being just of the width of the fifth, but rather longer than it, the seventh is very 
large, and is dilated both on the outer and inner sides, eight to ten are simple and 
rather elongate, while the apical joint is again dilated, being about as long as, but 
not so broad as, the seventh. 
Egypt. 5. 
cue 2U2 
