It could emit, at will, a certain portion of the water, and it appears, therefore probable that this fluid is taken in partly for the sake of regulating its specific gravity.

This Diodon possessed several means of defence.
It could give a severe bite, and could eject water from its mouth to some distance, at the same time making a curious noise by the movement of its jaws.

By the inflation of its body, the papillae, with which the skin is covered, become erect and pointed.

But the most curious circumstance is, that it secretes from the skin of its belly, when handled, a most beautiful carmine-red fibrous matter, which stains ivory and paper in so permanent a manner, that the tint is retained with all its brightness to the present day: I am quite ignorant of the nature and use of this secretion.

I have heard from Dr.Allan of Forres, that he has frequently found a Diodon, floating alive and distended, in the stomach of the shark; and that on several occasions he has known it eat its way, not only through the coats of the stomach, but through the sides of the monster, which has thus been killed.