SOUTH AMERICAN NEMATOGNATHI. 



77 



Maxillary barbel reaching little beyond base of pec- 

 toral, mental barbel not to gill-opening, postmental 

 barbel extending considerably beyond the gill-opening. 



Snout blunt, little decurved, 

 upper jaw little produced. Teeth 

 villiform, the intermaxillary 

 band emarginate on the sides 

 and behind; teeth on the roof 

 of the mouth in from 3-5 con- 

 fluent patches on each side; 

 vomerine patches separated from 

 each other. 



Gill-membranes meeting in an angle, forming a fold 

 across the isthmus. Gill-rakers 6-|-10. 



Distance of dorsal spine from tip of snout 2|-2| in the 

 length. Dorsal and pectoral spines granular in front, 

 striate on the sides, the dorsal spine scarcely roughened 

 behind, 1|-1-| in the head; the pectoral spine serrated 

 behind, its length about 1^ in the head. Space between 

 the dorsal and adipose fins 3 J in the length. Adipose 

 fin scarcely shorter than the dorsal, its posterior margin 

 free. 



Upper caudal lobe longer, falcate, 3|-4 in the length. 



Anal fin about as high as long, 2| in the head. 



Ventrals not reaching to the anal, about 2 in head. 



Color, in specimen No. 7702, light brown, silvery on 

 sides, white below; tip of dorsal and pectoral fins dusky; 

 all the fins more or less dotted with brown: all the other 

 specimens plumbeous above, white below; fins dusky. 



Head 3|-3f ; depth 5-5*; D. I, 7; A. 19. 



The specimens examined, .13-.48 m. long, are from 

 (7702) Campos; Rio Doce; Rio Grande do Sul, — (the 

 smaller specimens from this locality have the occipital 

 keel very strongly developed). 



A specimen from the Rio Grande do Sul, .42 m. long. 



