﻿Sijngnathus. gangetic fishes. ^ 15 



The head is not compressed. The gill-memhrane adheres all 

 round, and enth'ely closes the aperture. 



The hack is straight, and surrounded by a sharp ridge. An 

 obtuse angle runs along each side. The helhj is flat, and sur- 

 rounded by a sharp ridge. The lateral lines are indistinct, but 

 are in the middle of the upper face of the sides. The vent is 

 near the middle. Before it are sixteen joints, and behind it 

 thirty-two. 



The dorsal fin occupies two joints of the back and four of 

 the tail, and contains about thirty rays. The pectoral fins are 

 rounded, and each contains about fifteen rays. The tail fin is 

 oval, ends in a sharp point, and contains about seven rays ; but 

 their number cannot be distinctly traced. 



ORDER II. 



FISHES HAVING THE DORSAL SPINE OF BONE, AND WANTING 



VENTRAL FINS. 



L Genus. — Unibranchapertura. 



Fishes of the second order without pectoral fins ; with a 

 body shaped like a serpent, and having only one opening to 

 the gills situated under the throat. 



I have retained the name given to this genus by La Cepede, 

 although it is both long and barbarous, and need not have su- 

 perseded the Synhranchus given by Bloch, which, although far 

 from harmonious, is at least shorter. The name of La Cepede 



