Pimelodus. gangetic fishes. 205 



The back slopes forward in the same curve with the head. 

 The sides slope outward to the belly. The lateral lines run 

 with a little curvature along the middle of the fish. The shoul- 

 der-bones are naked and sharp. The vent, which is near the 

 middle, has two apertures. 



The foremost fin of the back slopes much behind, its edge 

 forming a concave curve. Its first ray is a short prickle, with 

 smooth edges. The second fin is much longer than that of 

 the vent, occupying almost the whole space between the first 

 fin and that of the tail. Its edge forms an arch, very low be- 

 fore, and higher behind. The pectoral fins are low, shorter 

 than the head, and sharp above. Each has about eleven rays, 

 of which the first is a strong prickle indented behind. The 

 ventral fins are rather shorter than the pectorals, and each con- 

 tains six rays, of which the first are simple. From the fifth 

 ray the fin behind the vent slopes both ways, before quickly, 

 behind gently ; the four first of its rays are undivided. The 

 upper lobe of the tail fin is considerably the longest, has its 

 edge more convex than that of the lower, and its end drawn 

 out to a slender point. 



33d Species. — Pimelodus aor. Plate XX. Fig. 68. 



A Pimelodus with the fin of the tail divided into two very 

 unequal lobes ; with eight tendrils, of which two reach to the 

 fin of the tail, and two to the end of the head ; with a smooth 

 body, nearly opaque, and brownish above ; with twelve rays 

 in the fin of the vent ; and with nine in the foremost of the 

 back. 



The Aor is common in the rivers of Bengal, and in the up- 

 per parts of the Gangetic estuaries, where the water is not very 

 salt. It grows to two or three feet in length, and is a lurid 

 animal ; but, by the natives, is considered very good eating. 



