132 prof. huxley on the oviducts of osmerus. [mar. 20, 

 Summary of British Species. 



1. Contributions to Morphology. Ichthyopsida. — No. 2. 



On the Oviducts of Osmerus ; with Remarks on the 



Relations of the Teleostean Avith the Ganoid Fishes. 



By Prof. Huxley, F.R.S. 



[Eeceived March 9, 1883.] 



Nearly sixty years ago, one of the most accurate and prolific of 

 modern anatouiisls and euibryologists, Rathke, published a memoir 

 on the alimentary canal and the reproductive organs of fishes^, which 

 is not the least valuable of its author's numerous and weighty con- 

 tributions to science. At p. 122 Ratiike writes : — "la certain fisiies 

 the oviducts have eutireiy disappeared ; this is the case in the Eel, 

 in the Sturgeon", in Cubitis tcenia, and iu the Lamprey. In others, 

 however, &uch as the higher kinds of Salmouoids, there extends back, 

 behind each ovary, a narrow liaud which may be regarded as the 

 remains of an oviduct. In all these fishes, therefore, the central 

 abdoiiiiiial cavity must take the place of the oviduct, as it receives 

 the eggs when they are detached, and allows them to make their 

 exit by a single opening at its posterior extremity. 



' H. Rathke, " Ueber den Darmkanal und die Zeugungsorgane der Fische," 

 Schriften der naturforschenden Gesellscbaft zu Danzig, Heft iii. Bnnd 24. 



- Rathke, taking the structure of ordinary osseous fisli as his standard, says 

 justly enough that the " oviducts [such as these flsh possess] have disappeared " 

 in the Sturgeon. In Cohitis harhatida the single ovary has an oviduct of Ihe 

 same character as in other Cyprinoid fishes. I have not e.Kamiued C. tainia, 

 about which, in other parts of his memoir, Rathke's statements are full and 

 precise. 



