SOUTH AMERICAN NEMATOGNATHI. 319 



aaa. Teeth on the intermaxillaries and on the mandible villiform, in bands, 

 those on the vomer conical, in a single series. (PSEUDOCETOPSLS). 



c. Eye moderately large, about 6 in the head; gill-opening as far above 

 as below the pectoral. Distance of the first dorsal ray from tip of 

 snout 3 in the length; ventral fins united by a membrane; pectoral 

 fins reaching in the<* beyond the base of the veiitrals. All fins im- 

 maculate. Head 5; dorsal 7; A. 22. (Kner.) gobioides 252. 



aaaa. Teeth all villiform. 



d. Teeth on the vomer in two patches; head 3J. Ventrals behind the 

 vertical, from the last dorsal ray, the basal half of the inner margin 

 joined to the ventral surface; posterior nares remote from each other. 

 Eye lOf in the head. Barbels all short. Gill-opening extending 

 above and below the pectoral fin. Distance of first dorsal ray from 

 tip of snout 2| in the length. Caudal somewhat forked; pectoral fin 

 reaching f toward the base of the ventrals. Depth 4; D.I, 6; P. I, 9; 

 V. I, 5; A. 29. (Steindachner). occidentals 2">3. 



dd. Teeth 011 the vomer in a single series; head 4f; width of the head 

 not more than half of its length; ventral fins connected by their inner 

 margins to the ventral surface. Barbels all short. Grayish, darker 

 above; basal half of the dorsal punctate with black. D. I, 6; A. 29; 

 V. 6; P. 10. (Gill.) ventralis 254. 



249. Cetopsis candiru, 



Sihtrus candiru Spix. Gen. Spec. Pise. 13, plate x, fig. 1, 1829 (Equa- 

 torial rivers of Brazil). 



Cetopsis candiru Agassiz, Gen. Spec. Pise. 13, 1829. 



Cetopsis candira Cuv. & Val. Hist Nat. Poiss.xiv, 386, 1839 (copied); 

 Giinther, Cat. Fish. Brit. Mus. v, 199, 1864 (Kiver Cupai); Cope, 

 Proc. Am. Philos. Soc. xvii, 678, 1878 (Peruvian Amazon); Stein- 

 dachner, Flussfische Siidamerika's, iv, 5, 1882 (Kio Huallaga); 

 Eigenm. & Eigenm. Proc. Cal. Acad. 2d Ser. i, 157, 1888 (Taba- 

 tinga; Jutahy, Tonantins; lea). 



Habitat: Amazons and tributaries from the Kio Cupai to the Kio 

 Huallaga). 



Subterete, little compressed and scarcely tapering 

 backward. Head short and thick, the bones everywhere 

 covered with thick muscle; profile somewhat arched in 

 front; the depth of the head a little less than the width; 

 anterior nares 1-J- times as wide apart as the posterior 

 ones. 



Eye small, but much larger than one of the posterior 

 mires. 



Barbels rather thick and short, at least partially re- 



