560 THE OCEAN WORLD, 
The skin of these fishes bristles with small slightly-projecting spines, 
the number of which compensate for their smallness, which repel 
their enemies, and even wound the hand that would grasp them. 
They enjoy, besides, a singular faculty: they can inflate the lower 
portion of their body, and give it an extension so considerable that 
it becomes like an inflated ball, in which the real shape of the animal 
is lost. This result is obtained by the introduction of an immense 
quantity of air into the stomach when it wishes to ascend to the 
Fig. 367.—Diodon pilosus. 
surface. The species of globe-fish are numerous (Fig. 366). One 
is common in the Nile, where specimens are frequently left ashore 
during the annual inundations. 
The species of Diodon (Fig. 367) differ from the sun-fish in the form 
of their bony jaws, each forming only one piece. ‘They seem to have ° 
two teeth, whence their name, from als, Zzvo, d30bs, teeth. They differ 
also in their spines, which are larger. ‘The fishes belonging to the 
genera Zétraodon and Diodon may be said to be the hedgehogs and 
porcupines of the sea. , 
There are many species of this genus—D/odon pilosus, represented 
in Fig. 367, will givean idea of the others. 
