330 On Aquatic Carnivorous Coleoptera or Dytiscide. 
204. Hydrovatus acutus, n. sp.—Latus, subtiliter reticulatus, subopacus, in elytris 
crebre evidenter punctatus, testaceo-ferrugineus supra leviter infuscatus; clypeo 
indistincte marginato, subtruncato; coxis posterioribus minus crebre fortiter 
punctatis. Long. 23, lat. 13 m.m. 
Mas, antennis longioribus ante medium incrassatis. 
Extremely similar to H. subtilis (No. 203), but with the incrassate joints of the male 
antennee different, the fourth and fifth joints being thicker than the others, while 
the sixth is a little and the seventh decidedly narrower than the preceding ones: 
the extremity of each wing-case is very slender and acuminate so as almost to 
form a spine. 
Celebes, (Jan., 1874, Beccari). Sumatra. 448. 
205. Hydrovatus fractus, n. sp.—Ferrugineus, latus, subnitidus, crebre fortiter 
punctatus, prothoracis lateribus subparallelis. Long. 2, lat. 13 m.m. 
The margin of the clypeus is extremely obsolete; the elytra are closely and 
coarsely punctured, the coxze not closely, and not so coarsely. The size is nearly 
that of H. cuspidatus (No. 180) but the form is not quite so broad in the middle. 
The antennze are very slender and quite simple; the front tibize not quite so broad 
as in H. cuspidatus. The species may be readily distinguished from its allies by. 
the difference in the outline when looked at from the sides, it is then seen that 
this insect has the thorax a good deal more parallel-sided, and the elytra are more 
curved in and contracted at the shoulders, so that the lateral outline of the thorax - 
and elytra is less continuous. EH 
Tam not at all sure of the sex of the individual described, the front tarsi are 
broad, but the basal joint is scarcely so broad as the following one. | 
Siam. 15. 
°206. Hydrovatus crassulus, n. sp. —Ferrugineus, nitidus, crebre. fortiter Pan 
tatus, convexus, sat latus, postice acuminatus. . Long. 25, lat. 13 m.m. 4 
A very convex species, a good deal sielller than H. clypealis (No.. 179). Whe 
antennee are moderately long and stout. The thorax becomes but little broader . 
towards the base, and the epipleural line of the elytra is much curved behind the : 
shoulder. The coxee are closely and coarsely punctured. | te 
Brazil, (Santa Rita, August 1850, Dr. R.-F. Sahlberg). 17. 
207. Hydrovatus parallelus, n. sp.—Angustulus, subparallelus, minus convexus, 
testaceus, subnitidus, sparsim punctatus, ad apicem breviter acutus. Long, ae 
lat. 1¢ m.m. Bt 
