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A Contribution to our Knowledge of the Ovary and 

 Intra-ovarian Egg in Teleosteans. 



By 



W. li. C'alderwood, 



Director of the Laboratory of the Marine Biological Association. 



With Plates XI and XII. 



The reproductive organs of Teleosteans liave been studied by 

 many writers. All observations^ however, appear to be either on 

 the organ as seen at only one season of the year, or on the early 

 maturation of the ovum and development of the embryo. I do 

 not in this paper concern myself with the primitive development 

 of the ovary, or the subsequent growth of the permanent ova 

 from the primitive ova or sexual cells of the embryo (1). My 

 attention is rather centred on the adult and mature organ in its 

 various conditions of sexual activity or repose. 



I have preserved and sectioned a series of ripening ovaries, 

 and have also turned my attention to the spent organ, and the 

 manner in which it again reaches the condition of what is some- 

 times known as sexual inactivity ; in this way completing what I 

 may call the adult ovarian cycle. 



I have examined the ovaries of the following species : — Pleuro- 

 nectes limanda, Trigla lyra, Trigla limanda, Labrax lupus, LopMus 

 piscatorius, Clupea finta, Ammodytes tohianes, Gadus seglijinus, 

 8olea vulgaris, Conger' vulgaris, and Merhiccius vulgaris. 



My most complete series of sections are of the ovaries of the 

 common dab {Pleuronectes limanda) and hake {Merluccius 

 vulgaris), forms readily procurable at Plymouth. The main 



results of this paper are, therefore, drawn from the examination 

 of these species, sections from the ovaries of the others being used 

 for comparison. 



Since the ovary is modified to suit the requirements of the 



