18 
GURNARDS. 
organ appears to be in some measure subject to tbe -will of 
the fish, aad also to be capable of sustaining the various 
degrees of pressure which it must encounter when these fishes 
rise, as they sometimes do, from a considerable depth in the 
water to the surface. 
The fish of this family are placed by Linneeus in the Thoracic 
order. 
AIR-BLADDERS OF TEIGLIDiE. 
Tubfibh. 
