out from numerous orifices regularly placed near 

 the surface ; and Dr. Monro has recorded his 

 discovery of a very elegant structure for the pre- 

 paration of this mucus between the skin and 

 muscles. The secretion is so viscid that it is 

 with great difficulty pressed out. There is a 

 species of carp the rex cyprinorum of Linnaeus 

 that seems to hold a middle place between the 

 rough and smooth skinned fish ; the upper part 

 and back is covered with scales, while these are 

 altogether wanting in the lower part and belly. 



The brain of fishes is smaller in relation to 

 their body than in other vertebral animals. It 

 does not exceed in the barbot the seven hun- 

 dredth, in the pike the one thousand three hun- 

 dredth, and in the tunny even the thirty-seven 

 thousandth part of the weight of the body ; but 

 still the nerves going from it are as large in pro- 

 portion to the several organs, as in the other 

 classes. 



Fishes have a firm and compact body, hea- 

 vier than the element in which they exist; and it 

 follows, that they would have sunk and remained 

 at the bottom, had not the Almighty provided an 

 apparatus by which they could rise and swim 

 about at pleasure. " Fishes are adapted," says 

 Richerand, " by their structure, to the element in 

 which they live ; the form of their body bounded, 

 every where, by salient angles, is well calculated 

 to separate the columns of a fluid. A bladder 

 filled with air, which is expelled at pleasure, 

 renders their specific gravity less than that of 



