346 



ORGANS OF NUDIBRANCHIATA. 



Ill Riz::olia pcrcgrina the reproductive organs are very 

 different to those of the other Eohdid?e studied ; even Tritonia 

 has organs more nearly approaching in structure those of Cahna 

 and Coryphclla. The most striking modification is that there 

 is no fertihzing chamber, and that the oviduct comes out of 

 the prostata, s« that the ova have apparently to pass through a 

 portion of this organ on their way to the anterior. The herma- 

 phrodite duct, almost as soon as it leaves the ampulla, swells into 

 a gland having the structure typical to the prostata, only later on 

 is the oviduct given off. At the apex of the blunt evertible 

 penis is situated another gland in the form of a number of pear- 



Fig- 5- 



shaped glands opening into a circular chamber with a small 

 aperture to the exterior. A feature of the structure of Rizsolia's 

 organs is the absence of long ducts connecting the various reser- 

 voirs, glands, etc. The ampulla, as already mentioned, is quite 

 closely connected to the prostata ; the latter in turn runs right 

 up to the penis ; the oviduct is very short, and the receptaculum 

 seminis opens directly into the vagina. That the organs were 

 mature was proved by the fact that the short, broad oviduct, 

 serving as a fertilizing chamber, was full of spermatozoa. 



In Bcrghia the reproductive organs are similar to those of 

 Ri.c.':;ol!a. The oviduct is fairly thin and long, and is filled with 



