198 SALMONIA. [SKVF.XTU DAY. 



and five or six feet perpendicular. He sis, when 

 they first rose out of the water upon the (try board, 

 they rested a little which seemed to be ml their 

 slime was thrown out, and sufficiently gi.'.,i ous, 

 and then they rose up the perpendicular asivut with 

 the same facility as if they had been rnov - , on a 

 plane surface. (Trans. Abr. vol. ix. p. 8ii. ; There 

 can, I think, be no doubt, that they are ;iisted by 

 their small scales, which, placed like those o. xvpents, 

 must facilitate their progressive motion:" 54 " t,u se scales 

 have been microscopically observed by Leueuhoeck. 

 (Phil. Trans, vol. iv.) Eels migrate from the salt 

 water of different sizes, but I believe never when 

 they are above a foot long and the great mass of 

 them are only from two and a half to lour inches. 

 They feed, grow, and fatten in fresh water. In small 

 rivers they are seldom very large ; but in large deep 

 lakes they become as thick as a mans arm, or even 

 leg ; and all those of a considerable size attempt 

 to return to the sea in October or November, 

 probably when they experience the cold of the first 

 autumnal rains. Those that are not of the largest 

 size, as I said before, pass the winter in the deepest 

 parts of the mud of rivers and lakes, and do not seem 

 to eat much, and remain, I believe, almost torpid. 



* [Relative to this opinion, and the following one. that the conger 

 and eel are not distinct species, see additional note at the end of the 

 volume. J. D.] 



