SOUTH AMERICAN NEMATOGNATHI. 215 



longer than the lower, teeth in upper jaw in a very deep 

 band, those on roof of mouth in two patches; barbels 

 fleshy; adipose fin shorter than anal; dorsal spine equi- 

 distant from snout and middle of adipose fin. Cau- 

 dal widely forked, the rays normal. 



ANALYSIS OF THE SPECIES OF SORUBIMICHTHYS. 



a. Upper part of body brownish, with uiimerous darker spots; maxillary 

 barbels longer than head. planiceps 156. 



an. Color of body nniforiD. 



b. Head, dorsal, pectoral and ventral fius with numerous black dots; 

 maxillary barbels extending to the ventrals; caudal lobes pointed; 

 pectoral with teeth along both margins. D. I, 6; A. 10. (Agassiz.) 



spatula 157. 

 hh. Uniform grayish brown, darker above. Head covered with skin; 

 maxillary barbels much shorter than the head, mandibulary barbels 

 still shorter; intermaxillary band of teeth broader than the vomerine 

 band, separated from each other by a very narrow interspace; dorsal 

 spine equidistant from snout and origin of adipose fin; adipose fin as 

 long as anal; caudal slightly forked. Head 3|; D. I, 6; A. 11. (Gtin- 

 ther.) rjigas 158. 



156. Sorubimichthys planiceps. 



Mystus No. 6, Artedi, in Seba, iii, 84, pi. 29, fig. 6. 



Mystusl^o. 386, " Gronow Zoophyl. 125." 



Plati/stoma planiceps Agassiz, Gen. Spec. Pise. Bras. 25, 1829 

 (Amazon; Solimoens; Rio Negro); Cuv. & Val. Hist. Nat. Poiss. 

 XV, 19, 1840 (Brazil); Schomburgk, Fishes of Guiana, parti, 187 

 (Rio Branco, not in Guiana); Kner, SB. Ak. Wien, xxvi, 400, 

 1857 (Rio Negro); Giinther, Cat. Fish. Brit. Mus. v, 106, 1864 

 (copied); Peters, MB. Ak. Berl. 469, 1877 (Calabozo). 



Sorubimichthys j^laniceps Eigenm. & Eigenm. Proc. Cal. Acad. 2d 

 Ser. i, 139, 1888 (Manacapuru; Teffe; Hyavary). 



Sorubim piranaca Spix, Gen. Spec. Pise. Bras. 25, plate xii, 1829. 



Platystoma artcdii Giinther, Cat. Fish. Brit. Mus. v, 106, 1864 

 (based on Artedi & Gronow); Vaillant, Bull. Soc. Philom. ser. 

 7, iv, 150, 1880 (Calderon). 



Sorubimichthys ortoni Gill, Proc. Acad. Nat. Sci. Philad. 1870, 94 

 (Peruvian Amazon). 



Habitat: Amazons, Orinoco and their tribiitaries. 



The specimens examined are from Manacapuru, 

 Hyavary and Teffe .51-. 70 m. 



The specimen from Teffe has the markings most dis- 



