[Illustration: DIODON.]
The curious Diodons differ from the Globe-fish in the form of their bony
jaws, each forming only one piece. They differ also in their spines,
which are much larger than those of the Globe-fish. These Fishes may be
said to be the Hedgehogs and Porcupines of the sea. Like the Globe-fish,
they can erect their spines and inflate their bodies.