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DIODON. 
This genus is found in all the tropical seas of the world ; its 
body is covered with spines ; the lish can swell itself out as a 
globe, and takes such an extraordinary appearance, that sailors 
and travellers are very apt to collect it, as an object of 
curiosity. There is no stronger proof of the semi-tropical nature 
of all the Australian seas than the frequent occurrence of these 
fishes in the most southern parts of this continent. Dr. Gunther 
limits this genus of Linnseus to the sorts who have “jaws without 
a medium suture, body covered with dermal ossifications, each 
with a pair of lateral roots, and with a stiff, moveable, and 
erectile spine ; nasal tentacle simple, with a pair of lateral 
openings.” 
nioDoir spiirosissiMUS. 
Diodon Spinosissimus, Ouvier, Mem. Mus., vol. iv., p. 34. 
It is with great doubt I place under this name the present 
fish, but having at my disposal no means of comparison, I 
prefer not complicating still more the synonyma of a family 
which requires already a special study, but I believe the 
number of admitted species will, when this takes place, be 
very much increased. General appearance of Diodon IListrix 
of Bloch ; nasal tentacle formed of a short simple tube, with a 
pair of lateral openings ; mouth small, its opening being less than 
the diameter of the orbit ; spines very numerous, long, slender, 
all of about equal length ; the root of each has three ridges ; the 
tail has no spine, but there is one rather stronger than the others 
on each side of the body at its base. Dorsal fin with twelve 
rays ; caudal elongate, of eight rays ; anal of the size of the 
dorsal, of twelve rays ; pectorals of twenty-two. 
The body is, on its upper half, of a light green ; the lower one 
is white ; on each side there are three faint black blotches of an 
irregular form ; the spines and fins are of a light yellowish 
green, those of the lower parts are white ; eye yellow ; no spots on 
the fins. 
I have two specimens, both about three and a-half inches 
long. 
