166 SEA-SIDE STUDIES. 



elusive observations, which assured me that ova and spenna- 

 tozoa were intermingled in the same stroma ; and the student 

 may easily verify these observations when informed that the 

 ova are distinguishable from the spermatic vesicles by their 

 darker colour ; he has only to spread out, on a glass slide, a 

 fold of the membrane containing the ova, and he will per- 

 ceive among them polyhedral and oval bodies of a paler 

 coloui' ; if these are crushed, the spermatozoa will be seen 

 escaping from them. 



How can this be reconciled with Kolliker's and Hollard's 

 statement of the sexes being separate ? If I could have 

 devoted the requisite time to the point, when specimens 

 were abundant, I might, perhaps, have answered positively, 

 what I can now only answer hypothetically. As it is, I 

 propound a suggestion, which the researches of some more 

 fortunate inquirer may confirm, or rectify. First, be it 

 remembered that the ova and spermatozoa are developed in 

 precisely the same portion of the lining membrane on the 

 free border of the septum. This is the statement of Kolliker 

 and Hollard, who further remark that it is only by the dif- 

 ference of colour that the testis is distinguished from the 

 ovary. If these anatomists found ova in one animal, and 

 spermatozoa in another, whereas I found both in one 

 and the same animal, four possible explanations suggest 

 themselves : 



1st. There are Actinia) in whom the ova and .spermatozoa 

 are intermingled ; that is to say, one grape-like cluster will 

 contain both kinds of cells. 



2d. There may be others in whom the spermatozoa accu- 



