570 ORDER PLECTOGNATHI. 



There is at the Cape an oblong species, Orthagoris- 

 cus oblongns, Bl., Schn. 97. the skin of which is hard, 

 and divided into small angular compartments. 



A third species has sometimes been taken in the 

 Ocean, very small, and which has some spines, Orth. 

 spinosus, Bl., Schn. Diodon mola, Pall. Spic. Zool. pi. 

 iv. f., and better Kcelr., Nov. Comm. Petrop. x. pi. 

 viii. f. 3. 



We shall also make a particular genus of the 



Triodon, 



Fishes whose upper jaw is divided as in tetraodon, and 

 the lower simple, as in diodon. An enormous dewlap, 

 (fanon,) almost as long as the body, and twice as high, 

 is supported in front by a very large bone which re- 

 presents the pelvis, and approximates them to certain 

 of the Balistes. Their fins are the same as in diodon ; 

 their body is rough, as in tetraodon, and the surface of 

 their dewlap bristles with a great number of small 

 rough crests placed obliquely. 



But one species is known, from the Indian Ocean, 

 discovered by M. Reinwardt, Triodon bur sarins, Reinw., 

 Triod. macroptere, Less, and Garn. Voy. de Duperrey, 

 Poiss. No. 4. 



The second family of the Plectognathi, or that of 



SCLERODERMES, 



Is easily distinguished by the conical or pyramidal 

 muzzle prolonged from the eyes, and terminated by 

 a small mouth, armed with distinct teeth, few in num- 



