4 
rRESlDI2NT’« ADDRESS. 
this Society, — c))itomising the important contributions to the life 
history of that lish made by continental observers, chiefly at the 
great Eel fishery of Commachio on the Adriatic. After briefly 
reviewing the various theories with regard to the reproduction of 
the fresh-water Eel advanced by naturalists, from Aristotle, who 
wrote four centuries before Christ, to almost the present time, he 
sliowed that it was not till the year 1777 that the female generative 
organs of the Eel were at length discovered and described by 
Carlo Mondini, of Bologna, the truth of whose observations were 
not fully admitted till finally confirmed by Bathke in 1850, to 
whose good fortune it fell to become possessed of the first and 
only specimen of a pregnant Eel, which so far had been seen 
by a naturalist. With regard to the male Eel, Mr. Southwell said 
it was not till the year 1842 that any decided opinion as to its 
sexual organs appeared, and then all the chief anatomists, misled 
by an appearance which he described, were of opinion that in the 
same Eel were found the reproductive organs of both sexes — that 
they were complete hermaphrodite^. It was not till Eovember, 
1873, that Dr. Syrski, of Trieste, virtually solved the problem ; but 
it remained for Dr. Jacoby in 1877 to establisli the trutli of 
Dr. Syrski’s observations, and fully describe the organ which had 
been discovered by the latter and called after his name. In no 
case up to the present time has an individual of the fresli-watcr 
Eel of either sex been discovered in which the sexual organs were 
fully developed. After describing the reproductive organs in each 
sex of the Eel, and by means of dissections showing them in situ, 
as well as e.xhibiting them more fully by means of enlarged draw- 
ings, ]\Ir. Southwell called to his aid Mr. F. Kitton, who by means 
of the microscope exhibited a beautifully-mounted slide which he 
had prepared, showing a small portion of the ovary of an Eel in 
which the ova and their contents were distinctly visible, thus 
removing any doubts as to the nature of the organ which had just 
been seen in the flesh. The result of repeated and long-continued 
observation and experiment leads to the following conclusions — 
that for the development of their organs of generation. Eels need 
