V28 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



Hombaum-HornschucJi, 1 who re-ecboes Bathke's erroneous assertions, 

 claims to have found in the fringed bodies of many eels ? instead of eggs, 

 round bodies inclosing small granules, and has declared tbat such eels 

 are male individuals. 



Schlilsser 2 was not able to confirm Hornbaum-Hornscbucb's assertion. 



I have found only once, and that in an eel 390 millimeters long, dis- 

 sected on the 5th July, in the fringed organs, besides eggs, the above- 

 described small bodies in compartments similar to those of the testicles 

 of eels and other fish. 



The rare phenomenon of spermatic compartments and ovarian leaflets 

 occurring side by side, I also found once in OpMdium barbatum and Smarts 

 alcedo, where the compartments were interlarded with groups of eggs. 



Professor Sieboldf after having passed in review the different hypotheses 

 regarding the male organs of reproduction in the eel, and having reached 

 a negative conclusion, says that eels may reproduce by means of 

 parthenogenesis, or by being of different sex, or also by being her- 

 maphrodites. 



In 1872 was published a memoir, 4 accompanied by an illustrative plate, 

 by Prof. Gr. B. Ercolani, in which the author distinguishes, as a rudi- 

 mental testicle, the fat which is found attached to the swimming-bladder 

 between the intestine and the right ovary and the intestine itself/while 

 he calls " true testicle " a sac on the left side, formed exceptionally by 

 the peritoneum, and found in the place which corresponds to the posi- 

 tion of the fat on the right side. In the parietes of this sac, Professor 

 Ercolani found fat and self-moving spermatozoa, which movements, 

 however, seem to be nothing else but the molecular movement of the 

 granules found so frequently in the tissues of the animal body. I have, 

 instead of all this, found in the same place a fatty formation, resembling 

 that of the right side, and only in two eels have I found a sac which 

 could be inflated through the genital opening. 



The so-called alveolar or proligeuous cells of the testicle are, therefore, 

 — as the illustration in Ercolani's article also shows — nothing else than 

 the common and well-known alveolar vessels of the adipose' tissue. 



In the same year (1S72) was published the results of researches by 

 O. Balsamo Crivelli and L. Maggif professors at the University of Pavia, 

 who, contrary to the assertions of Professor Ercolani, maintained that the 

 fat on the right side was a well-developed testicle, and that of the left 

 an atrophied testicle. They, too, have therein found, and also given 

 illustrations of, spermatozoa. . 



1 De Anguillaruin sexu ac generatione. Gryphiae, 1842. 



2 De Petromyzoutuni et Auguillaruui sexu. Dorpati, 1849. 



3 Die Siisswasseriische vou Mittel-Europa, p. 348. Leipzig, 1863. 



4 Del perfetto ermafroditismo delle anguille. Meruoria del Prof. Coram. G. B. Erco- 

 3aui, uelle Memorie dell'Accademia delle Scienze dell'Istituto di Bologua. Serie iii, 

 tomo i, fascicolo 4. Bologua, 1872. 



5 Iutorno agli organi esseuziali della riproduzione delle anguille &c. uelle Memorie 

 <lel Reale Istituto Lombardo di Scienze e Lettere, vol. xii-xiii, della serie iii, fasci- 

 ola 4. Milauo, 1872. 



