198 CLASSIFICATION OF FISHES. 



fishj which they grind with ease by means of their 

 strong enamel jaws or hard teeth. As a passage from this 

 to the next sub-famiiy^ we arrange the singular shaped 

 Triodon hursarius Reinw. (^fig. 32.), for it partakes of 

 the general structure both of one group and the other. 



(175.) The Diodonince, or globe-fish, have the jaws 

 not only destitute of any apparent teeth_, but are even 

 without any divisions, so that each remains as one entire 

 piece ; yet behind their cutting edges, however, is a 

 shghtly rounded protuberance, marked by regular fur- 

 rows, which supplies the place and office of grinding 

 teeth : the form of the body is more globose than in any 

 of this order ; and, when distended, becomes, in some 

 species, absolutely round : they are all armed with nu- 

 merous long and acute spines, of which, as M. Cuvier 

 observes, ahorse chestnut is a good miniature resemblance. 

 These fishes are confined to the tropical and warm 

 latitudes, chiefly of India ; and none seem to exceed a 

 very moderate size. The gills are five in number, and are 

 very slightly developed. The globe-fish, as well as 

 the tetraodons, are remarkable for the power of inflating 

 their body like balloons, to an enormous size, by swal- 

 lowing the air, and thus filhng their stomach. This is 

 obviously a means of defence against their enemies ; 

 M. Cuvier, indeed, remarks, that, when thus inflated, 

 they turn topsy-turvy, tbe stomach being uppermost, 

 and they float to the surface, without being able to 

 direct themselves. This, however, seems somewhat im- 

 probable, and by no means according with what we should 

 naturally expect from fish so well provided with the 

 means of actively repelling their enemies. The follow- 

 ing account of the Diodo.i Mstrioo L., by Dr. Hamilton, 

 seems a much more natural relation of its habits. ^' This 

 fish is said to aflbrd an amusing spectacle when taken by 

 a Hue and hook properly baited with some small crab or 

 other crustaceous animal : after having played round the 

 bait for some time in various directions, it seizes it with 

 a sudden spring ; but finding itself hooked, it exhibits 

 every appearance of the most violent rage, inflating its 



