go FISH GULTURAL ASSOCIATION. 
begin when at the end of the Middle Ages, the prohibition which 
the veneration for Aristotle had thrown over the investigations 
of learned men was thrown aside. With the revival of the natural 
sciences in the sixteenth century we find that investigators turned 
themselves with great zeal to this special question. There are 
treatises upon the generation of the eel written by the most re- 
nowned investigators of that period, such as Rondelet, Salviani, 
and Aldrovandi. Nevertheless, this, like the following century, 
was burdened with the memory of the numerous past opinions 
upon the eel question, and with the supposed finding of young 
inside the body of the eel. 
The principle supporters of the theory that the eel was vivi- 
parous, were Albertus Magnus, Leuwenhoek, Elsner, Redi, and 
Fahlberg. The naturalists, Franz Redi and Christian, Franz 
Paullini, who lived in the seventeenth century, must be men- 
tioned as the first who were of the opinion, founded, however, 
upon no special observations, that the generation of the eel was 
in no respect different from that of other fishes. 
In the eighteenth century it was for the first time maintained 
that the female organs of the eel could certainly be recognized. 
It is interesting that the lake of Comacchio was the starting 
point for this conclusion as well as for many of the errors which 
had preceded it. The learned surgeon, Sancassini, of Comacchio, 
visiting an eel fishery at that place in 1707, found an eel with its 
belly conspicuously enlarged; he opened it and found an organ 
resembling an ovary, and, as it appeared to him, ripe eggs. 
Thereupon he sent his find, properly preserved, to hie friend, the 
celebrated naturalist, Valisneri, professor in the university of 
Padua, who examined it carefully and finally, to his own great 
delight, became satisfied that he had found the ovaries of the eel; 
He prepared an elaborate communication upon the subject, 
which he sent to the Academy at Bologna.* 
At the very beginning there were grave questions raised as to 
the correctness of this discovery. The principal anatomical 
authority at Bologna, Professor Valsalva, appears to have shared 
*T fail to find any record of the publication of this paper, except that given by Jacoby, who 
States that it was printed at Venice, in 1710 with a plate, and subsequently, in 1712, under the 
title ‘‘ Di ovario Anguillarum,”’ in the proceedings of the Leopold Academy. 
