Description of a collection of Fishes from China. 403 



With species corresponding in their general form and size 

 as the Siluri of Cuvier do, mistakes may occasionally arise • 

 from the difficulty of distinguishing one from another.* 



CossYPHus,f Nov. Gen. 



Gen. Char.^ — ^The head broad and covered with a flat 

 helmet, the dorsal and anal long, and continuous with the 

 caudal% an arboraceous appendage to the second and third 

 branchial arches; eight cirri; two transverse rows of minute 

 crowded teeth in the upper, and a single row in the lower jaw. 



COSSYPHUS ATER. t. xxii. fig. 3. 



The length from the hinder process of the helmet to 

 the snout, equal to one-third part of the length of the body. 

 The helmet terminates behind by a round short process in 

 front of the dorsal, and has an oval depression between the 

 eyes ; the eyes are small and lateral. The pectoral spine is 

 not so long as the fin; but it is strong, and has the front 

 edge thin and finely serrated ; the operculum is small ; eight 

 rays in the branchial membrane ; the openings to the bran- 

 chiae are situated low ; the branchial combs are four, the 



* Calcutta Journ. Nat. Hist. vol. II. p. 583. It is remarked that 

 Silurus duda, Canio, and Chechra, Buch. are but one species. The 

 Chechra may however be conceived to be a variety of S. bimaculatus, 

 BL, and is distinguishable from S. duda by its dorsal spine being serra- 

 ted on the hinder margin. There is also a typographical error in the 

 characters of the species noted, the pectoral rays being given as 3, 

 instead of ^ . 



13 



t From KO(T(JV(j>og, the Greek name of an unknown kind of dark- 

 coloured fish. 



X In Cossyphus ater, the specimen from which the genus is described, 

 and the only one that is known, the caudal was removed from the end 

 of the tail, and its place left vacant by an open fissure. 



