DIODON, in ichthyology, a genus belonging to the order of amphibia nantes. The jaws are bony, stretched out, and undivided; the aperture or mouth is a transverse
transverse line. The body is every way beset with sharp moveable prickles. It has no belly-fins. There are two species, viz. 1. The tringa, which is spherical, and has triangular prickles. It is a native of India. 2. The trystrix, which is oblong, with cylindrical prickles, and is a native of the Cape of Good Hope.