Macropteronotus. gangetic fishes. 145 



ward, and is rather small. The under jaw is shortest. The 

 lips are fleshy, and the upper has no bones. In both jaws are 

 numerous crowded sharp granular teeth. The tongue is blunt, 

 smooth, and tied down. The foremost aperture of each nos- 

 tril, placed at the end of the nose, is tubular ; the hinder one 

 is half way between the former and the eye. The eyes are 

 placed forward on the crown of the head, but far from each 

 other, are small and round, with circular pupils. The gill- 

 covers move freely, consist of one plate covered with skin, 

 smooth, and ending in a point behind. The membranes of the 

 gill-covers are exposed to view, but are so thick, that the num- 

 ber of rays, which each contains, cannot be exactly determined. 

 Under the lower jaw is a transverse slit. 



The sternum, or breast-bone, is naked, and marked with 

 transverse lines like the teeth of a comb. The lateral lines 

 run straight along the middle of the side, and are smooth. 

 The vent is before the middle. 



There are seven fins covered with thick skin, but their rays 

 are visible. That of the back reaches from very near the head 

 to very near the end of the tail. Its rays, which are soft, 

 branched, and recurved at the end, gradually lengthen a little 

 toward the posterior end, which is rounded. The pectoral fins 

 are low, small, and blunt, although their rays are longest above 

 the middle. The first ray in each is a strong sharp prickle, 

 not indented on the edge. The ventral fins are small and near 

 each other, and each contains six soft rays. The fin behind 

 the vent extends from near that organ to the end of the tail, 

 and resembles that of the back. The tail fin is rounded. 



1st Species. — Macropteronotus jagur. 

 A macropteronotus with the back fin united to that of the 

 tail. 



T 



