SOUTH AMERICAN NEMATOGNATHI. 471 



Head 3|; depth 2|-2|; D. I, 7-8; A. 7; V. 6; P. 1,8. 

 Lat. pi. II . 



Three specimens .05 m. Rio Doce; Rio Parahyba. 

 Thayer Expedition. 



460. Corydoras seneus. 



Hoplosoma leneum Gill, Syn. Fish. Trinidad, 43, 1858 (Trinidad, 



W. I.). 

 Callichthys ceneus Gtinther, v, 230, 1864 (copied). 

 Corydoras wneus Jordan, Proc. U. S. Nat. Mus. 1886, 560 (name 



only). 

 Habitat: Trinidad. 



This species is known only from the types. 



461. Corydoras armatus. 



Callichthys armatus Giinther, Proc. Zool. Soc. Lond. 1868, 230, fig. 



1 (Xeberos and HnallagaJ. 

 Gasterodermus armatus Cope, Proc. Amer. Philos. Soc. xvii, 681, 1878 



(Nauta). 

 Corydoras armatus Eigenm. & Eigenm. Proc. Cal. Acad. 2d Ser. i, 



166, 1888 (name only). 

 Habitat: Maraiion and its tribiitaries. 



462. Corydoras paleatus. 



Callichtys pu7iciatus {not ot Bloch), Valenciennes, Voy. d'Orbigny, 

 ix, Atlas ii, pi. v, fig. 1, 1847; Cuv. & Val. xv, 318, 1840 (? Suri- 

 nam ; Monte Video). 



Callichthys paleatus Jenyns, Voy. Beagle, iv, 113, 1842 (loc. ?); 

 Giinther, v, 230, 1864 (copied); Hensel, Wiegm. Arch. 1870, i, 

 71 (Porto Alegre). 



Corydoras pakalus Eigenm. & Eigenm. 1. c. (Uraguay). 



Corydoras marmoratus ^teindachnev, Denk. Ak.Wien, 1879, 26, pi. 

 V, fig. 1 (La Plata). 



Habitat: La Plata and tributaries. 



As the description oi paleatus exactly describes Stein- 

 dachner's plate of marmoratus and our specimens, we 

 have identified marmoratus with paleatus. 



Body short, chubby; ventral outline almost straight; 

 profile steep, evenly arched; occipital tapering into a 

 pen-shaped occipital process; fontanel elongate. 



Eye Ih in the snout, 31- in the head, 1| in the interor- 

 bital. Snout acute. Rictal barbels not extending be- 



