TENTH ANNUAL MEETING. 97 
ered structure is actually the long sought male organ of gener- 
ation. The investigator cannot, however, answer this question 
with complete certainty, since the thing which, is most necessary 
to the solution of this question, namely, the finding and the 
recognition of the spermatozoa, has not yet been accomplished. 
In February, 1879, Professor Packard announced the discovery 
of spermatozva in eels from Wood’s Holl, Mass., but soon after 
declared that this was a mistake, and that he had been deceived 
by molecular movements among the yolk nuclei in the female 
organs. The discovery of spermatozoa in the spermaries of the 
conger-eel, recently announced by Dr. Hermes, of Berlin, is, 
however, sufficient to demonstrate fully the correctness of Syr- 
ski’s theory. The confirmation in the case of the common eel is 
solely a matter of time. 
HOW TO DISTINGUISH MALE AND FEMALE EELS. 
INTERNAL CHARACTERISTICS.—BENECKE AND SYRSKI. 
The differences between the organs of sex in the eel are well 
described by Benecke. The ovaries of the eel are two yellowish 
or reddish-white elongate organs as broad as one’s finger, situ- 
ated alongside of the backbone, arranged in numerous trans- 
verse folds, extending through the entire length of the abdomi- 
nal cavity. They have no special opening to the outside of the 
body, and their contents must be discharged into the abdominal 
cavity and must find exit through the very small opening situ- 
ated behind the anus. These two bodies, on account of their 
great size, are of course not easily overlooked, but they contain 
such a great quantity of fatty cells and the eggs imbedded in 
them are so small and delicate that one might easily believe, 
even after a superficial microscopic examination, that the whole 
organ consists only of fat. While the eggs of other fishes meas- 
ure from one to three millemeters in diameter—and sometimes 
are much larger—still the eggs in the ovary of the eel have, on 
an average, a diameter of about one millemeter, and are so closely 
surrounded by fatty cells with outlines much more strongly 
marked that it requires great skill to prepare a microscopic slide 
in which they shall be as plainly visible as they are in the 
