XXXIII.— LECTURE ON THE ORGANS OF REPRODUCTION AND 

 THE FECUNDATION OF FISHES AND ESPECIALLY OF EELS.* 



By Dr. Syrski. 



INTRODUCTION. 



The subject which I propose to speak of on this occasion is " On the 

 organs of reproduction of fishes, and especially of eels", a subject belong- 

 ing to zoology. 



Every one knows what this word means, and its derivation is quite 

 clear, viz, from the Greek word "zoowP, a living being, an animal, 

 and " logos ", a word, a rational discourse. Any further definition of 

 this branch of natural science might therefore seem superfluous. And 

 still we hear people call " zoology " what is taught in the lower classes of 

 our " real-schools " as well as what is studied in the higher courses of the 

 university. Most people understand by this name the description of the 

 external forms of animals. In general, by zoology is meant a descrip- 

 tion of animals. 



In the first place, it is only an exposition of some zoological data ; in 

 the second place, it is the expression of what is known of the inner life oi 

 animals during a certain given period, and indicates a simple period in 

 the development of zoology, the standard of the first and last develop- 

 ment, L e., the genealogical as well as philogenetic and individual develop- 

 ment of animals, the conformity of their outer forms to their inner organi- 

 zation, of their functions, of the mutual relations between them and the rest 

 of nature, and finally the manner in which man makes use of them. Zo- 

 ology therefore embraces soogeny, treating of the origin of animals; philo 

 geny, i e., the development of the species ; ontogeny, also called embry- 

 ology, i. e.,the development of the individual being; morphology, which 

 treats of the form ; anatomy, which relates to structure ; physiology, which 

 concerns itself with functions, and which, in a wider sense, also comprises 

 ontogeny, the geographical distribution of animals, and their uses. 



The classification of animals according to their affinities, being noth- 

 ing but the result of a knowledge of the animals, must therefore natur- 

 ally be modified as this knowledge increases. 



Some also comprise zoology together with botany, mineralogy, geoh 

 ogy, paleontology, in some cases even geography, under the common 

 name natural history, only applying the designation natural science to 



* Degli organi della riproduzione e della fecondazione dei pesci ed in inspecialit& 

 delle anguille, in Bollettino della Sociela Adriatica di Scienze naturali in Trieste, No. 

 1, pp. 10-32, December, 1874. Trieste, 1875. 



