94 



FISH GALLERY. 



The Gymnodontes contain the genera Triodon, Tetrodon, Diodon, 

 and Orthagoriscus. The Globe-fishes (Tetrodon and Diodon) have 

 a short, thick, cylindrical body, more or less studded with spines ; 

 they possess the power of inflating their body by filling their dis- 

 tensible oesophagus with air, thus assuming a more or less globular 

 form, the spines protruding and forming a defensive armour, as in the 

 hedgehog ; therefore they are frequently called " Sea-hedgehogs. - " 

 [Case 25.] In these fish, as in the others of the same family, the bones of the 



Fiff. 84. 



Rough Sun-fish {Orthagoriscus mola). (Captured near Portland.) 



upper and lower jaws are confluent, forming a beak with a trenchant 

 edge, without teeth. The Sun-fishes {Orthagoriscus, figs. 84, 85) 



