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FISH GALLERY. 



median suture, however, and appear as two great teeth, whence the 

 name 'Diodont' (see jaws 956). There is no spinous dorsal fin, 

 nor pelvic fins. The body is inflatable (fig. 95) ; there are 

 movable bony spines in the skin, and in the long-spined species the 

 spines stand out from the skin when the belly is inflated with air, 

 although otherwise they slope backward. This capacity of erection 

 of the spines has gained for the Diodont fishes the name of 



Fig. 95. — Porcupine-fish, Diodon maculatus; as swimming and 

 when inflated. 



Sun-fish. 



' Porcupine-fishes/ Two specimens of the common Porcupine- 

 fish, Diodon hystrix, are shown (958-959). the upper specimen 

 in a state of inflation, the lower in the condition in which the fish 

 swims about. Several other species are shown (961-966). The 

 Diodontidse are confined to tropical seas. 



In the Suu-fishes (family Molidse) the teeth are coalescent, 

 forming beaks ; these have no median suture. The swim-bladder 

 is absent and the body is non-inflatable. The body is short and 



