726 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



Conrad Gesner (sixteenth century 1 ) attributes the reproduction of 

 eels to putrefying matter, and also to copulation. 



MalpigM (seventeenth century 2 ), a great anatomist and expert micro- 

 scopist, declares that the ovaries not only of the eels but also of similar 

 fish, such as the "grongo" and the i4 murena" {Murama helena), are fatty 

 productions, and calls them " striae adiposes? 



Eedi (toward the end of the seventeenth century 3 ), who has dissected 

 many eels and "inurenas," (Murcerta helena), and also illustrated as such 

 the ovaries of the last-mentioned fish, nevertheless, does not recognize 

 the ovaries of the eel. 



He opposes the hypothesis that the eel can be reproduced from putre- 

 fying matter; he proves, moreover, that what are called young eels are 

 nothing but intestinal worms, and that therefore eels are not viviparous 

 animals, but are reproduced by means of eggs'in the same manner as 

 other fish. 



LeeuicenhoeJc (toward the end of the seventeenth century 4 ), who has 

 occupied himself much with microscopic observations, and was the 

 first who made known the infusoria, having found, in the urinary bladder 

 of an eel, very small parasitic worms, mistook them for young eels, and 

 the bladder itself for the uterus. 



Gcorg Eisner 5 relates that a fish- vender showed him an eel whose 

 uterus was full of young ones, which, to quote his own words, hwrebdnt 

 in diversis membranis involulce anguillw. 



Yallisneri (beginning of the eighteenth century 6 ) has given illustra- 

 tions of the true ovaries of the eel, but, following Malpighi and Eedi, 

 calls them vasi adiposi [fatty vessels]; and, having accidentally found 

 in an eel a pathologically-deformed swimming-bladder, announced with 

 great joy to the Academy of Bologna and the whole scientific world 

 that he had found the true ovary of the eel. 



Linne 1 maintains that eels are viviparous. 



Carlo Mwndini, 8 professor of anatomy at the University of Bologna, 

 was the first discoverer of the ovary of the eel, of which he gave a 

 detailed description to the Academy of Bologna the 19th day of May, 

 1777, which, however, was not published till 1783. 



Otto Milller 9 writes, in 1780, that he has found eggs in the fringed 



1 Conradi Gesneri Historise animalium liber iv. Tiguri 1558. 

 2 Tetras epistolarum, &c. DissertatiodeOinento, 1665. 



3 Osservazioni iutorno agli auimali viventi che si trovano negli auimali viventi. 

 Floreut. 1684. 



4 Arcana naturae. Epistola 75. An. 1692. 



6 Acad. Cass. Leopold. Miscellanea medico-pbysica. Observat. 119, p. 219. 

 6 Pritnaraccolta d'osservazioni &c. Venice, 1710. — De ovario anguillaruin. Epbeme- 



rides Acad. Nat. Curios, ad Centur. I et II appendix, p. 152, fig. h; An. 1712. — La terza 

 volta lo stesso: Nuova scoperta delle uova, ovaje delle anguille &c. nelle opere Fisico- 

 Medicbe, raccolta del suo figliulo. An. 1733. 



7 Systenia naturte, 1750. » 



8 De anguillae ovariis. De Bononiensi Scientiaruni et Artium Institute atque Acade- 

 mia Conimentarii. Vol. vi. 1783. 

 •Scbriften der Berliner Gesellscbaft naturforscbender Freuude. Vol. i, p. 204. 1780. 



