522 
THE OCEAN WORLD. 
for some time more or less soft, becomes finally hard. The chief cha- 
racteristic of the order is that the maxillary is firmly attached to the 
side of the intermaxillary bone which forms the jaw, and the arch of 
the palate is united to the shnll in such a manner as to be motionless. 
The operculum and rays of the gills are hidden under a thick skin, 
which leaves externally only a small branchial slit. These fishes 
have no true ventral fin, and have only vestiges of side fins. 
This order comprehends two natural families characterised by the 
armature of their jaws. They are the Gymnoclonia and the Sclero- 
dermoid. 
Fig. 356 . The Globe-fish (Orthogorbcus), anti Rnn-flsh (’retraction). 
In the family of Gyvinodonta the jaws have no apparent teeth, 
but they are furnished with a species of beak in ivory, which repre- 
sents them. The Sun-fish, Tetraodon (Fig. 356), belong to the 
family. 
The Globe-fish are so named from their large head and bony salient 
jaws, which are each divided in front by a sort of vertical slit in two 
portions, which simulate two teeth. These four portions of bony j» ff > 
which project beyond the bps, somewhat resemble the hard and dentate 
jaws of the turtle. Their anterior part is sometimes prolonged, like the 
