On Aquatic Carnivorous Coleoptera or Dytiscidce. 811 



foveolis frontalibus minus profundis ; antennis nigris, articulis basi, primis fere totis ferrugineis. 

 Prothorax fortiter transversus, niger , limbo crebre sat fortiter pmictato, disco parum convexo subtevi ; 

 basic medio triangiilariter productus, angiilis posticis rectis ; lateribus tenuiter marginatis, cum capita et 

 elytris fere in eodem arcu rotimdatis. Elytra protliorace quintuple longiora, lateribus sequaliter minus 

 fortiter rotundata, apice panim acuminata ; disco leviter convexo, tenuissime fusco-pubescentia, nigra sat 

 nitida, crebrius evidenter punctata, seriebus punctorum majorum impressis sat discretis, prseciijue 

 interiore. Corpus subtus nigrum, fere glabrum, sterni lateribus et abdominis basi punctatis. Pedes picei, 

 genubus, tarsisque dilutioribus." 



It is possible this species may prove to be the same as Dytiscus nigrita (No. 561). — D. S. 



1435. Hydroporus submuticus, Thoms., Op. Ent. VI, p. 537. Sweden. 



" Elougatus, glabriculus, niger, pedibus piceo-rufis ; cajjite majusculo, foveolis obsoletis ; prothorace 

 anguiis posticis subrectis, limbo elytrisque crebrius punctatis." 



" H.elongatulo affinis sed major, magnitudine fere H.lapponum, foveolis frontalibus obsoletioribus,elytris 

 veutreque basi minus profunda punctatis discedens. Caput majusculum, nigrum, vertice et antice piceum 

 obsolete parceque punctatum, foveolis frontalibus parvis hand datarminatis. Antennre prothoracis basin 

 paullo superantes, nigricantes, basin versus ferruginese ; articulis secundo tartio longiora, hoc quam 

 quarto baud transvarso sesqui longiora. Prothorax lateribus cum elytris haud continuo rotundatis : basi 

 colaopteris vix angustior, medio late productus, anguiis posticis leniter obtusis ; margins lateral! tenui, 

 antrorsum pai-um angustato, haud rotundato ; glaljer niger, crebrius punctatus, disco Isevi. ]<]lytra 

 lateribus pone macUum vix dilatata, apice subattenuata : nigra, basi et limbo lateral! dilute fnsco-j>iceis, 

 hoc linea nigra lateral! ; supra vix pubescentia, minus crebre, subtiliter punctata, seriebus e punctis 

 majoribus haud conspicuis. Corpus subtus nigrum, segmentis 3 primis lateribus sat crebre, minus 

 profunda punctatis ; prosterno antice inter basin coxarum processu parvo palpos excipianta, instrncto. 

 Pedes piceo-rufi." 



1436. Hydroporus subtilis, Lee, Ann. Lye. V, p. 206. California. 



" Oblongus, postice subacutus, piceus, subtiliter punctatus, nitidus, capita parce punctulato, thorace 

 antrorsum angustato, rvifo, antice posticeque nigiicante, lateiibus paulo rotundatis, tenuissime margi- 

 natis, cum elytris angixlum vix formantibus, striola basal! profunda ; elytris macula quadrata jione 

 humerum, altaraque marginal! pone medium rufis, stria suturali distincta. Long. -06, specimen unicum 

 ad Sta. Isabel." 



According to a specimen recently communicated to me by its describer, this species is to be placed in 

 Bidessus, group IV ; the elytra possess a rather obscure sutural line ; it may go near No. 261. — D. S. 



1437. Hydroporus subtonsus, Lee, Proc. Ac. Phil., 1855, p. 297. North America. 



" Longior ovalis, parum convexus, parca pubescens, niger, ora rufescente, thorace lateribus, vix margi- 

 natis mfescentibus cum elytris angulum obtusum formantibus, anguiis posticis rectis, disco parce subtilius, 

 ad basin et latera distiactius punctato, elytris ssepe testaceo-piceis, modice punctatis, pedibus rufo-testaceis. 

 Long. -125." 



" Lake Superior and Vermont. Resembles in appearance H. varians and H. puberulus, and likely to 

 be confounded with them. H. varians is naiTower and more oblong, the sides being almost parallel at 

 the middle, and is entirely glabrous. H. puberulus has the posterior angles of the thorax obtuse and 

 very distinctly impressed. The elytra of the female are less shining and less deeply punctured than those 

 of the male." 



This is placed by Crotch next to D. tristis (No. 602).— D. S. 



TKANS. ROV. DUB. SOC, N.S., VOL. IL 5 M 



