plectognathi. 273 



Triodon, Cuv. 



We also make a separate genus of these fishes, whose upper jaw is 

 divided as in Tetraodon, and the lower one single, as in Diodon. An 

 enormous dewlap, almost as long as the body and twice as high, is 

 supported before by a very large bone which represents the pelvis 

 and approximates them to certain Balistes. Their fins are those of 

 a Diodon, their body is rough as in Tetraodon, and the surface of 

 their dewlap is covered with numerous, small, rough crests, placed 

 obliquely. 



T. hursarius, Reinw.j Triod. macroptere, Less, and Garn., 

 Voy. deDuper., Poiss. No. 4. The only species known; it was 

 discovered in the Indian Ocean by M. Reinward. 



FAMILY II. 



SCLERODERMI. 



The second family of the Plectognathi is easily distinguished 

 by a conical or pyramidical snout, prolonged from the eyes 

 and terminated by a small mouth, armed with a few distinct 

 teeth in each jaw. The skin is usually rough or invested with 

 hard scales ; the natatory bladder is oval, large, and strong. 



Balistes, Lin.(l) 



The body compressed; eight teeth in a single row in each jaw, ge- 

 nerally trenchant; the skin scaly or granulated, but not exactly os- 

 seous; the first dorsal composed of one or more spines articulated 

 with a particular bone which is attached to the cranium, marked by 

 a furrow into which they are received; the second dorsal long, soft, and 

 placed opposite to a nearly similar anal. Although the ventrals are 

 wanting, a true pelvic bone is observed in the skeleton suspended 

 to the shoulder. 



These fishes abound in the torrid zone, near rocks and on the sur- 

 face of the water, where they display their brilliant colours. Their 

 flesh, which is but lightly esteemed at all times, becomes, it is said, 



(1) Balistes, a name given to these fishes by Artedi, from their Italian appella- 

 tion Pesce balestra, which is itself derived from a supposed similitude between the 

 motion of their great dorsal spine and that of a cross-bow. 

 Vol. II.— 2 K 



