2/10 THE BONY FISHES AND GANOIDS 



member of the family which commonly ascends rivers to any distance. When taken 

 in the larger rivers its flesh is excellent for the table, great quantities being sold in 

 the Calcutta market, where it is commonly known by the name of cockup. The allied 

 genus Psammoperca is represented by two species, one ranging from Australia to 

 China, while the other is exclusively Australian. There are many other generic 

 representatives of this extensive family, which are far too numerous to mention, no 

 less than twenty-seven occurring within the limits of British India. Among these 

 the Indian genus Pristipoma, which is referred by some writers to a separate 

 family, is represented by extinct species in the middle Eocene of Italy; and it may 

 be mentioned here that the earliest known forms of the family are the extinct gen- 

 era Podocys and Acanus from the lower Eocene of Switzerland. 



THE SCALY-PINNED FISHES Family 



Nearly allied to the perches, the beautiful tropical fishes, designated scaly- 

 finned fishes, are so named on account of the characteristic feature of the median 

 fins being more or less thickly covered with small scales. In addition to this dis- 

 tinctive feature, these fishes are characterized by the deep and compressed form of 

 the body, on which the scales are either ctenoid or entire, and the continuous lateral 

 line, which stops short of the tail fin. The mouth, which is generally small, is 

 placed at the extremity of the muzzle, and has a distinct lateral cleft, and the eyes 

 are on the sides of the head. The small teeth are arranged in bands, and there are 

 neither tusks nor incisors. The soft portion of the single dorsal fin is rather longer 

 than the spinous; the anal has three or four spines; the lower rays of the pectorals 

 are branched; the pelvic pair are thoracic in position, with one spine and five 

 soft rays, and the scaling of the median fins causes them to pass imperceptibly into 

 the body. The great majority of these curious and beautiful fishes are inhabitants 

 of tropical seas, and are very generally found in the neighborhood of coral reefs; 

 but some ascend estuaries and tidal rivers, although but a comparatively-short dis- 

 tance. All are carnivorous, and of relatively-small size, while they are but seldom 

 used for food. The three genera of which examples are represented in our illustra- 

 tion are those in which the zebra-like coloration attains its most marked and strik- 

 ing development; and for the beauty and singularity of their adornment these fishes 

 are almost unequaled. Out of a large number of existing genera it is to these that 

 our attention will be chiefly directed, and it may be remarked that the whole of 

 them are met with in the Indian seas. Extinct species of zebra fish belonging to 

 existing genera are found in the middle Eocene of Italy, among these being the 

 Indian and Australian genus Toxotes. An extinct genus has been recorded from 

 the Cretaceous of Westphalia. 



The typical genus CKatodon belongs to a group of genera in which 

 there are no teeth on the vomers or palatine bone, while the spines of 

 the dorsal fin are not separated from the soft rays by a hollow or notch, and there 

 is no spine to the preopercular bone; the genus in question being particularly dis- 

 tinguished by the short or moderately-long muzzle, and the approximately uniform 



