SOUTH AMERICAN NEMATOGNATHI. 257 



half of the anterior margin with fine teeth, the entire 

 posterior margin with larger teeth. Space between dor- 

 sal and adipose fins 4 in the length; the adipose fin 

 longer than high, shorter than the dorsal iin. 



Caudal fin deeply forked, the lobes about as long as 

 the head. Anal fin emarginate, the anterior rays highest. 



Ventral fins not reaching the anal. 



Pectoral fin reaching to base of ventrals or slightly 

 farther, little longer than the dorsal spine. 



Light brown above, silvery on sides and below; ful- 

 crum of the dorsal spine blackish ; tips of the first dorsal 

 rays dusky; sometimes the middle caudal rays, sometimes 

 a narrow bar on each lobe of the caudal, sometimes the 

 anterior half of the ventrals dusky. 



Head 3|-3|: depth 5^-; lat. 1. 34+3; D. I, 6; A. 13; V. 

 7, P. I, 9. 



Fifteen specimens .065-. 16 m. Manaos; Rio Negro; 

 Hyavary ; Manacapuru ; Teffe ; Obidos ; Tabatinga. Thayer 

 Expedition. 



196. Hemidoras stlibelii. 



Oxydoras s<w6e/«' Steiudachuer, Flussfische Siidamerika's, iv, 5, pi. 



iii, figs. \-\h, 1882 (Rio Huallaga). 

 Hemidoras st'dbelii Eigeum. & Eigenm. Proc. Cal. Acad. 2d Ser. i, 



158, 1888, 

 Habitat: Huallaga. 



197- Hemidoras morei. 



Oxydoras morei Steindachner, 1. c. ii, 6, pi. i, figs. 2-2a, 1881 



(Rio Negro). 



Hemidoras tnorei Eigenm. & Eigenm. Proc. Cal. Acad. 2d Ser. 



i, 158, 1888. 

 Habitat: Rio Negro. 



198. Hemidoras humeralis, 



Doras humeralis Kuer, SB. Ak. Wien, xvii, 1855, 140, pi. iv, fig. 6 



(Barra do Rio Negro). 

 Corydoras humeralis Heckel MS. Kner, 1. c. 

 Oxydoras humeralis Giinther, Cat. Fish. Brit. Mus. v, 206, 1864 



(copied). 



17 



