168 gangeTic fishes. Order V. 



ward a large bony plate, which covers the fore part of the back 

 and the hind part of the head, and is marked with waved lines, 

 On the nape, as from a centre, there diverge, in different direc- 

 tions, several straight lines. On the centre of the fore part of 

 this plate is an oblong cavity, sharp at each end ; and behind 

 the eye the plate forms into four separate ridges, one of which, 

 on each side, passes to the nostril, and the other two re-unite 

 on the nose. Behind the plate has also four short processes, 

 one on each side, running down the shoulder 5 and another on 

 each side of the first ray of the back fin. The two tendrils, 

 from the sides of the upper jaw, are almost as long as the head, 

 and the four from the chin are shorter. The mouth is of mode- 

 rate size, placed under the extremity of the nose, and extend- 

 ing straight backward. The under jaw is the shortest, and in its 

 middle has a slight longitudinal ridge. In each jaw are many 

 granular teeth. On the palate are two bones covered with sharp 

 crowded teeth. The apertures of the nostrils are near each 

 other, and about half way between the eyes and jaw. The fore- 

 most aperture is circular ; the hinder crescent-shaped, and 

 covered by a reflected membrane. The eyes are of moderate 

 size, high, and forward ; and the pupils are oblong. Each gill- 

 cover consists of one plate, which exposes to view a membrane 

 containing four flattened bones. Under the chin is a slit. 



The back forms a sharp ridge. The sides slope outward, and 

 on each shoulder, above the blade, which is naked, there is an 

 oblong protuberance. The lateral line descends from the upper 

 side of this protuberance, is smooth, and very distinctly mark- 

 ed. The vent is behind the middle. The tail is dilated at the 

 extremity, and ends in a notch. 



The first fin of the back is far forward, and slopes very rapid- 

 ly from the point of the second ray to the end. The first of 



its rays is a very short bone j the second is a strong prickle, 



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