784 On Aquatic Carnivorous Coleoptera or Dytiscide. 
1327. Hydrocanthus nanulus, Lec., New. spec. Col. I, 1863, p. 22. North America. 
« Hlongato-ovalis, postice paulo magis attenuatus, rufo-testaceus, nitidus, impunctatus, elytris paulo 
saturatioribus, antennis pedibusque pallidioribus. Long. :05.” 
“Louisiana; Dr. Schaum. The very small size at once distinguishes this from all other species of the 
genus; it is more regularly oval, and less convex than the others.” 
1328. Hydrocanthus rubripes, Boh., Eugen. Res., p. 19. Monte Video. 
“ Oblongo-ovalis, convexus, niger, nitidus, postice modice attenuatus ; capite, antennis, prothorace ad 
latera confuse pedibusque rubris ; elytris tribus minorum punctorum seriebus leviter impressis. Long. 
24, lat. 12 m.m.” 
“Summa similitudo H. nigrini, semper dimidio fere minor, presertim brevior, posterius minus 
attenuatus. Caput ferrugineum, nitidum leve, postice parum infuscatum, apice utrinque puncto profundo 
impressum. Palpi ferruginei. Oculirotundati, modice convexi, glauci. Antenne ferruginee. Prothorax 
longitudine duplo latior, apice late, leviter rotundato-emarginatus, basi utrinque subsinuatus, medio breviter 
sub-triangulariter productus, lateribus tenuiter reflexo-marginatis, pone apicem leviter rotundato-ampliatis, 
angulis anticis antrosum prominulis, acutis, posticis fere rectis; superne convexus, niger nitidus, 
extrorsum plus minusve late, confuse ferrugineus, levis, antice postice et ad latera subtiliter punctulatus, 
Scutellum nullum. Elytra antice subtruncata, prothorace non latiora at illo fere duplo et dimidio longiora, 
pone basin apicem versus sensim angustata, apice conjunctim subacuminata; nigra, nitida, extrorsum 
interdum confuse ferruginea, singulo seriebus tribus e punctis parvis, sat crebris notato ; margine inflexo, 
ferrugineo. Corpus subtus nigro-piceum, nitidum, subtiliter, crebre punctulatum. Pedes rufo- 
ferruginei.” 
This is no doubt a Canthydrus, and is perhaps allied to C. brevicornis (No. 45).—D. 8. 
1329. Hydrocanthus socius, Sahl., Act. Soc. Fenn. II, 2, 1844, p. 516. Rio Janeiro. 
“‘Qblongo-ovatus, postice angustato-acuminatus, ferrugineo-testaceus; elytris ad basin thoracis 
latitudine, brunneis, testaceo-irroratis, sutura apiceque obscurioribus, capite et thorace fulvescenti testaceis. 
Long. 1# lin., lat. 13 lin.” 
“Statura et magnitudo H. levigati. Caput convexum, fulvo-testaceum, subnitidum, leviusculum. 
Oculi magni, grisei, medio nigri. Palpi et antenne testacea. Thorax fulvo-testaceus, nitidus, glaber, 
antice parum infuscatus, longitudine sua plus duplo latior, antice late emarginatus, angustior, angulis 
subacutis, lateribus parum rotundatis, postice latior, angulis subrectis, basi sinuatis, in medio breviter 
sed acute productus, supra levis, punctis paucis ad marginem anteriorem subtilissimis. Scutellum non 
conspicuum. Elytra elongata, antice thoracis latitudine, usque ad medium sensim rotundato-dilatata 
versus apicem angustato-acuminata, brunnea, testaceo-irrorata, sutura apiceque obscurioribus, margine 
inflexo testaceo, pilis raris versus apicem albescentibus sparsis. Corpus subtus testaceo-ferrngineum 
abdomine infuscato. Pedes testacei.” 
This may possibly be a small species of Hydrocanthus near H. debilis (No. 78), or a Canthy- 
drus.—D. S. 
1330. Hydrocanthus testaceus, Boh., Res. Eugen.,p. 19. China. 
“‘Qblongo-ovalis, postice attenuatus, convexus nitidus, rufo-testaceus ; prothorace levi, antice postice- 
que tenuiter infuscato ; elytris impunctatis. Long. 2, lat. 1} m.m.” 
“Statura H. nigrini, multo minor, aliter coloratus. Caput modice convexum, rufo-testaceum, nitidum 
leve. Palpi rufo-testacei. Oculi rotundati, parum convexi nigri. Antenne rufo-testacee. Prothorace 
longitudine duplo latior, apice late, leviter rotundato-emarginatus, basi utrinque sub-sinuatus, medio 
