7? T H E P H I L O S O P H Y 



The bodies of moft fifhes are covered with a ftrong, thick, fkin, iti 

 which numberlefs fcales are inferted in an imbricated form, or like 

 tiles on the roofs of houfes. Many of tliem, and particularly thofe 

 which are fliaped like the cod, the trout, and the haddock, have a 

 longitudinal line on each fide. In thefe lines there are a number 

 of fmall duiSs or apertures, which throw out a mucous fubftance 

 that lubridates their fkins, and feems to anfwer the fame purpofes as 

 the mucous glands or dutfts placed in moft of our internal organs. 



Fiines are deftitute of hands and feet. Their progreffive motion, 

 therefore, is performed in a manner different from that of quadru- 

 peds and birds. Their inftruments of motion are fins, or machines 

 confifting of a number of elaftic beams, connedted to one another 

 by firm membranes. Their tails are of the fame texture. Their 

 fpine is remarkably flexible toward the pofterlor part of the body, 

 and here the ftrongeft mufcles are likewife inferted. They have a 

 power of contrading and dilating their tails at pleafure ; by which 

 means, and by the affiftance of the fins, they move forward in the 

 fame manner as a boat with oars on its fides and a rudder at its 

 ftern. Fifhes have no neck: As they feek their food in a horizon- 

 tal pofition, and can move their bodies either upward or downward, 

 a long neck would neceflarily have impeded their motion through 

 the water. 



The form of fifhes is extremely various ; and, if their hiflory 

 were fufficiently known, the connediion between their flrudture and 

 their manners would be equally apparent as in the other tribes with 

 which we are better acquainted. Some fifhes are long and cylin- 

 drical, as the fea-ferpent, and all the eel-fhaped fpecies. The eel- 

 kind, from their figure, are enabled to trail their bodies along the 

 bottom, and to conceal themfelves below the fand or mud. Others 

 are lefs cylindrical, and proportionally fhorter, as the mackrcl, the 

 3 - cod, 



