136 MEMOIRS OF THE CARNEGIE MUSEUM 



Galeichthys emphysetus Jordan, Proc. U. S. Nat. Mus., IX, 1886, 559. 

 Tac/iiSMTOs emp/it/seitts, EiGENMANN and EiGENMANN, Proc. Cal. Acad. Sci., (2), I, 



1888, 144; Occasional Papers Cal. Acad. Sci., I, 1891, 53. 

 Arius physacanthus Vaillant, Bull. Mus., d'Hist. Nat., V, 1899, 155; Nouv. Arch. 



Mus. d'Hist. Nat., (4), II, 1900, 128, pi. 7, fig. 1-lc (French Guiana). 



I have examined the type of emphysetus in the Berlin Museum and five speci- 

 mens, 250-500 "mm., Georgetown market. (C. M. Cat. No. 1487, 1735, 2486; 

 I. U. Cat. No. 12110.) I have not been able to find any specimens in the Berlin 

 Museum from Guiana. The type from Surinam is undoubtedly identical with the 

 specimens described below and with Vaillant's physacanthus. 



Head 3.8; depth 5.75; D. I, 7; A. 17 or 18; adipose fin 9.5 in the length; eye 3 

 in the snout, 4 in the interorbital, 10 in the head. 



Head depressed forward, the snout broad ; width of the head at the rictus equal 

 to the greatest depth; dorsal plate shield-shaped, its pointed anterior end fitting 

 into the notched occipital process, its width 1.3 in the width of the skull behind the 

 eyes; occipital process about half as wide as broad; surface of dorsal plate pitted; 

 occipital process with rows of nodules, the median row being most prominent; 

 skull striate to in front of eye; maxillary barbels reaching past base of ventrals; 

 outer mental barbel to middle of pectoral. Teeth all small, those of the roof of 

 the mouth in four contiguous patches, the palatine patches large, subcircular. 



Basal half or more of the dorsal spine swollen, its length equal to the width of 

 the head at the eyes or the opercle; anterior half of the swollen part of the dorsal 

 spine tuberculate, the part beyond with recurved notches both in front and behind; 

 pectoral spine about equal to the dorsal spine, the outer margin tuberculate to 

 near the tip, where it is notched, the posterior surface serrate; caudal deeply 

 forked, the upper lobe longer, 4 in the length; anal emarginate. 



Bluish gray above, white below; tips of dorsal, pectorals, ventrals and anterior 

 part of anal dusky. 



16. Sciadeichthys proops (Cuvier and Valenciennes). (Plate V, fig. 2; 



Plate VI, figs. 1-3.) 

 Bagrus proops Cuvier and Valenciennes, Hist. Nat. Poiss., XIV, 1839, 457 

 (Antilles; Guiana; Surinam; Porto Rico). — Muller and Troschel, in Schom- 

 burgk, Reisen, III, 1848, 627 (Waini and Barima). — Kner, SB. Akad. Wiss. 

 Wien, XXVI, 1857, 386 (locality ?). 

 Arius proops GtJNTHER, Catalogue, V, 1864, 148 (copied). 



Netuma proops Bleeker, Ichth. Arch. Ind. Prodr., I, 1858, 67; " Silures de Suri- 

 name," 1864, 62, pi. 7, pi. 12, fig. 2 (Surinam). 



