8 DESCRIPTIONS OF NEW SPECIES. 



are strongly acuminate at tip, and the alternate elytral spaces are 

 marked with an irregular series of large punctures. 



23. P. dissectlis. Rufo-piceus, thorace latitudine longiore, ovato, la- 

 teribus valde marginatis, basi medio emarginato utrinque obliquo, an- 

 gulis posticis subrectis, elytris planiusculis fortiter marginatis obsolete 

 striatis, interstitio 3io 4-punctato, apice oblique sinuatis ; antennis arti- 

 culo 3io 4to sesqui longiore. Long. "4 3. 



Nebraska ; Dr. Hayden : Texas ; Mr. S. B. Buckley. Also re- 

 sembles P. larvalis, but the 3d joint of the antennae is much 

 shorter. This species by its intermediate character necessitates 

 the union of Rliadine Lee. with Platynus. 



24. P. opactllus. Depressus, niger, thorace latitudine breviore, an- 

 tice et postice angustato, lateribus rotundatis, inargine fortius refiexo pi- 

 ceo, angulis posticis obtusis subdentiforrnibus, basi utrinque late impres- 

 so, et vix punctulato, elytris planiusculis thorace fere duplo latioribus 

 basi fere truncatis, striis angustis, interstitiis planis, 3io tripunctato ; 

 pedibus nigro-piceis, antennis capite cum thorace paulo longioribus, pal- 

 pisque rufo-piceis. Long. *50. 



Ohio ; Mr. Ulke. In appearance this species resembles P. de- 

 cern, but it differs very much from that and from every other 

 known to me by the characters given above ; it is intermediate 

 between that species and P. cincticollis. 



25. P. clesiteias. Piceus, nitidus, thorace convexiuscnlo, subcordato, 

 latitudine baud breviore, postice angustato, lateribus postice vix sinua- 

 tis, angulis posticis obtusis baud rotundatis, ad basin punctatoet utrin- 

 que fovea parva impresso, linea dorsali vix distincta, elytris elongato- 

 ovalibus thorace latioribus basi subtruncatis, striis antice profundis, 

 interstitiis paulo convexis, 3io bipunctato, antennis palpis pedibusque 

 pallidis. Long. *32. 



Nova Scotia; Mr. Ulke. Also very different from any other 

 species seen by me; the elytra have but two dorsal punctures, the first 

 is placed in the third stria, one-fifth from the base ; the second is in 

 the second stria about the middle ; I can perceive no vestige of a 

 third dorsal puncture in three specimens before me. 



26. P. silbsoriceiBS. Cupreo-aeneus, viridi-micans, thorace latitu- 

 dine vix breviore, subquadrato tenuiter marginato planiusculo, angulis 

 posticis obtusis rotundatis, basi utrinque profunda breviter impresso 

 et parce punctulato, elytris thorace paulo latioribus basi truncatis, 



