270 On Aquatic Carnivorous Coleoptera or Dytiscide. 
32. Canthydrus ovatus, n. sp.—Breviter ovalis, sat convexus, nitidus, ferrugineus, 
elytris obscurioribus, crebre fortiter punctatis. Long. 2¢, lat. 15 m.m. 
This species is intermediate between Suphis gibbulus (No. 38) and Canthydrus 
insularis (No. 35), it is smaller and shorter than the former, and has the coxal 
laminze more sparingly punctured; while it is less short and rotund than 
Canthydrus insularis, and has the antennse shorter. I have seen only one female; 
it has the apical ventral segment impressed on each side so as to appear distinctly 
carinate along the middle. 
Brazil, (Santa Rita, September, 1850, Dr. Sahlberg). 513. + 
33. Canthydrus grossus, n. sp.—Ovalis, posterius acuminatus, convexus, nitidus, 
testaceus, elytris sordidis, cum thorace sat crebre fortiter punctatis. Long. 4 m.m., 
lat. 23 m.m. 
In this species the thorax is even more closely and distinctly punctured than are 
the elytra. The large size readily distinguishes the species from its allies. The 
only specimen I have seen appears to be a female, and has the apical ventral seg- 
ment simple. 
Brazil, (Pernambuco, Brussels Museum). 512. 
34. Canthydrus rotundatus, n. sp.—Subrotundus, convexus, testaceus, nitidus, 
elytris sordidis, obsolete punctatis; prosterni processu  profunde canaliculato ; 
coxarum laminis parce punctatis. Long. 1s m.m., lat. 1s m.m. 
_ I have seen but a single individual of this minute species, its very short rotund 
form, and the diminished punctuation readily distinguish it. 
Brazil, (Pernambuco, Brussels Museum). 511. 
35. Canthydrus insularis, n. sp.—Brevis, rotundato-ovalis, convexus, nitidus, 
rufo-testaceus ; elytris obscurioribus, crebre, fortiter sed haud argute punctatis. 
Long. 2, lat. 1g m.m. 
The male has the apical ventral segment nearly simple. Though I have seen 
but a single individual I have no doubt it is distinct from though very closely 
allied to the preceding, being larger, of more rotund and convex form. 
San Domingo, (Coll. Bouvouloir). 510. 
36. Canthydrus punctipennis, n. sp.—Ovalis, brevis, latiusculus, sat convexus, 
nitidus, ferrugineus, elytris crebre fortiter punctatis, Long. 2s, lat. 13 m.m. 
The sexual characters appear to be the same as in Noterus bicolor (No. 37); 
