for multiplying F//7j. i6j 



of the procefles for accomplishing this end, which T there 

 pointed out, are not fufceptiblc of' analytic, and therefore 

 cannot be introduced into this tfiay ; it will be fufflcient for 

 me to fay, that the report of Lncepedc, Cuvicr, and Teffier, 

 was entirely in their favour. At prefent, I am {till more 

 convinced of the efficacy of the means which I then pro- 

 pofed; and I have no doubt that, if artificial ponds were 

 formed on the edges of rivers, the experiment would be at- 

 tended with complete fuccefs. Every man who catches a 

 fjfh, fays Dr. Franklin, diaws from the water a piece of 

 money. Let not the maxims and example of this philofo- 

 pher be lo't to pofterity ; let them rather produce fruit, like 

 itrong and vigorous feed Town in a fertile foil. Having ob- 

 fcbveu in New England that the herrings afcended from the 

 fea into one river of that country, while a fingle individual 

 was never fetfn in aiu)ther river, feparated from the former by 

 a narrow tongue of land, and which communicated alio with 

 the fea, this philofopher took the leaves of forne plants on 

 which the herrings had depohted their ova, already fecun- 

 dated, and conveyed them to the river which was deprived 

 of the annual vifit of thei'c ii(h. The fuccefs of this experi- 

 ment furpailed his expectation ; the ova were completely 

 productive, and the following year the river was peopled with 

 a numerous ihoal of herrings^ which lince th^t time have 

 continued to frequent it. 



This fifh is not the only one which I with to fee natural- 

 ized in frefh water; to the herring I fhould add feveral fpe- 

 cies of the pluronectes, fuch as the brill, the barbue, and 

 other flat fifth, which, poffeffing traits of the family of the 

 flounder, have alio fimilar wants and habits: I fhould add 

 alfo the mullet, the goby, the whiting, the' gar-fifh, and 

 perhaps one or two fpeeies of the gurnet. I would pay the 

 greateft attention poffible to the nature of the water proper 

 tor each fpt ries. This happy choice is tlte principal condi- 

 tion, and that which could enfure fuccefs; but I wov.kl felect 

 in particular lor this colonization the fifth found in lakes, 

 which, though little known, are more numerous thsn is 

 commonly fuppofed, and ought to be fo. 



At the epoch of the grand revolutions of the globe, when 

 a part of the primitive earth emerged from the middle of the 

 ocean, and pieces of water were formed without any current, 

 the fpeeies of tithes were varioullv dilperl't-':. Every lake in 

 Switzerland and Bavaria pofteiV fpeeies fo peculiar to 



it as not. to be found in anv neighbouring lake. Confined 

 within their narrow bafons, thete infulaTed fpeeies lead a 

 ni>'!ane! e fort of life, almoli exiled' from the 



L % world. 



