Order V. gangetic fishes. 137 



cies of Cyprinus have very strong affinities with each of these 

 intermediate genera, while the Silurus has very little affinity with 

 any of them, except the Salmo. In this view, the whole of these 

 genera, with their subdivisions, as detailed by La Cepede, forms 

 a connected circle, which, contrary to the order of writing, has 

 neither beginning nor end. In treating of them, therefore, sys- 

 tematically, the naturalist, with equal propriety, may begin with 

 any genus ; but he must finish with one nearly allied to the ge- 

 nus with which he commenced. This will serve my purpose, 

 as including all the genera of this oi'der which I have observed 

 in the Ganges, although authors describe several that are quite 

 anomalous, and that have no affinity to any of those connect- 

 ed in the circle. 



I begin with the genera, comprehended by Linnaeus under 

 the term Silurus, very properly subdivided by La Cepede, as 

 comprehending too many species. The fishes of this kind 

 may be distinguished by having a very slimy skin, destitute 

 of scales, and by having either two fins on the back ; or, if 

 they have only one fin, it is either united to that of the tail, 

 or is destitute of rays, or placed far forward, or is very long. 

 The genus Cobitis, allied to these fishes, has only one short 

 fin on the back, and it is supported by rays, and placed either 

 on the middle of the back, or immediately behind it. 



Besides these general characteristic marks, there are some 

 peculiarities to be observed in many of the species, although 

 all are not common to every species. 



None of these fishes have the bones in the upper lip called 

 mystaces by some authors. Some, indeed, in place of these 

 bones, have small cartilaginous elongations, but they are of 

 such trifling dimensions as to attract little or no notice. In 

 none of these fishes do the jaws profrude in opening, and all 

 of them have two apertures in each nostril. All these fishes 



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