456 CALIFORNIA ACADEMY OF SCIENCES. 



barbel extending to near the end of the ventrals; pectoral spine ser- 

 rate within, with short bristles without. Eye 3| in the head. Head 

 3; D. 8; A. I, 6; V. 7; P. I, 8. Lat. pi. f . (Cope.) 



melampterum 448. 



446, Hoplosternum littorale, 



CalUchthys llttoralis Hancock, Zoological Journal, iv, 244, 1828 

 (Demarara); Giinther, Cat. Fish. Brit. Mus. v, 227 (Demarara, 

 British Guiana; Trinidad); Liitken, Vidensk. Medd. 1874, 

 215 (Trinidad); Vaillant, Bull. Soc. Philom. series 7, iv, 155, 

 1880 (Calderon); Steindachner, Flussfische Siidamerika's, iv, 0, 

 1882 (Kio Huallaga); Jordan, Proc. U. S. Nat. Mus. 559, 1886 

 (name only). 



Hoplosternum littorale Eigenm. & Eigeum. Proc. Cal. Acad. 2d Ser. 

 vol.i, 164, 1888 (Surinam; Gurupa; Para; Saiitarem; Tabatinga; 

 Arary; Silva, L. Saraca; Villa Bella; Porto do Moz; L. Hyaim- 

 ary; Ueranduba). 



Callichthys subulatus Cuv. & Val. Hist. Nat. Poiss. xv, 311, 1840 

 (Cayenne; Buenos Ayres). 



Callichthys Iceviyatus Valenciennes, Voy d'Orbigny, ix, atlas ii, plate 

 v, fig. 2, 1847; Cuv. & Val. 1. c., 314, 1840 (Buenos Ayres; 

 Trinite); Kner, SB. Ak. Wieu, xvii, 1855, Ichthyol. Beitr. 109 

 (no locality). 



Hoplosternum hvvigatum Gill, Ann. Lye. Nat. Hist. New York, 

 1858, vi, 396 (Trinidad); Bleeker, Silures de Suriname, 24, 1864 

 (Surinam). 



Callichthys albidus Cuv. & Val. 1. c. 316 (Cayenne). 



Hoplosternum stevardii Gill, 1. c. 401 (Trinidad). 



Habitat: Rio Plata to Trinidad and Eio Huallaga. 



Depth everywhere greater than the width. Head 

 longer than broad, about as long as broad in the very old; 

 its depth 1J-1J in its length; profile evenly convex, 

 transverse profile arched; fontaiiel oval or pear-shaped 

 with a bridge across its center, the posterior opening be- 

 coming nearly obsolete in the adult. Suborbital bones 

 and opercle exposed, the former wider than the orbit in 

 the adult. 



Eye circular, equidistant between end of snout and 

 margin of opercle, 3J in the snout, 8 in the head, 5 in 

 the interorbital. 



Inner barbel longer, extending about to the tip of the 

 pectoral spine, shorter in the very old. Snout depressed, 



