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PLECTOGNATHI. — ^^BALISTIDAE. 
Family II. Balistid^e. 
{File-fishes,) 
In this Family the muzzle from the eyes on- 
ward is conical, or pyramidal in form, terminating 
in a small mouth, with distinct teeth in both 
jaws. The skin is either rough and marked with 
lines or scorings crossing each other at definite 
angles, or else covered with angular bony plates. 
The air-bladder is large, strong and oval. There 
are one hundred and ten species known, all 
natives of the warmer seas ; and they form two 
Sub -families. 
1. Balistina. The File-fishes. In these the 
body is compressed, more or less oval, and covered 
with a granulated, hard, leathery skin, marked 
all over with a scored pattern of lozenges, the 
crossing lines being perfectly smooth, while the 
rest of the skin is rough. They have eight teeth 
in one row in each jaw. 
2. Ostracionina, The Trunk-fishes. These have 
the body angular, four or three-sided, covered 
with angular plates of solid bone soldered to- 
gether, and forming a sort of indexible box, with 
openings for the mouth, the fins, the tail, and 
the gill-aperture. They have ten or twelve 
conical teeth in each jaw. 
Genus Balistes. (Linn.) 
The body, which generally assumes an oval 
form, more or less pointed at each end, and often 
compressed, is invested with a leathery skin, 
