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THE TRIGGER-FISH. 
In the genus Ostracion, of which the Horned Trunk-fish, or Coffer-eish, is a good 
example, the body is either three or four-sided, and covered with a solid coat of mail formed 
of six-sided plates or scales, and pierced with holes, through which protrude the mouth, the 
tail, and the fins. The whole of the interior structure is modified in accordance with this 
external and inflexible cuirass ; and on comparing the general form of this creature with that 
of certain reptiles, the analogy between the Coffer-fish and the tortoise is too close to escape 
observation. None of these fishes are in request as articles of food, their flesh being small in 
quantity, and in some species even thought to have a poisonous effect ; but the liver is very 
large, and yields a tolerable 
supply of oil. All the Coffer- 
fishes are natives of the tropical 
seas, and but few species are 
known. 
We come now to a very 
odd-looking fish, called per- 
force, for want of a popular 
title, the Oreosoma, a name 
framed from two Greek words, 
and literally signifying hilly - 
bodied. 
This remarkable little fish 
was captured in the Atlantic 
by Peron, and lias ever been 
esteemed as one of the curiosi- 
ties of the animal kingdom. 
Upon the body there are no 
true scales ; but their place is 
supplied by a number of bony 
or horny protuberances, of a 
conical shape, and serving no 
ascertained purpose. These 
cones may be divided into two 
distinct sets, the larger set being- 
arranged in two ranks, four on 
the back and ten on the abdo- 
men, and among them are placed 
the smaller set. The body of 
this fish is very deep, in pro- 
portion to its length ; and the operculum has two ridges, terminating in flattened angles. 
There are two dorsal fins, the first armed with five spines. 
The Trunk-fishes are common objects in the tropical waters of Florida. The Cow-fish is a 
familiar one. Trigger-fishes, allied forms, are also abundant. 
The very curious Trigger-fish is an example of the moderately large genus Balistes , 
inhabiting the warmer seas of many parts of the world, and which, on account of their rough 
and fierce exterior, are sometimes called File-eishes, or Leather-jackets. 
The name of Trigger-fish is derived from the peculiar structure of the dorsal fin. When 
the fin is erected, the first ray, which is very thick and strong, holds its elevated position so 
firmly, that it cannot be pressed down by any degree of force ; but if the second ray be 
depressed, the first immediately falls down like the hammer of a gun-lock when the trigger is 
pulled. The mechanical structure of these curious rays is extremely interesting, but the 
description would occupy too much space to be inserted in this work. 
A strong feeling against the flesh of this fish exists among sea-faring men, but, like many 
HORNED TRUNK-FISH . — Ostracion cornutus. (One-quarter natural size.) 
