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within the so-called ovarian-cell. As long as the bags remain 

 within the cell, the germinative vesicle and germinative dot are 

 distinctly seen in each egg. But by and by the bags are 

 pushed out of the cell, and as each bag is surmounted by a tuft 

 of from four to six tentacles surrounding a small opening, they 

 were mistaken by M. Loven for real Polyps, and called by him 

 female Polyps. But it is evident from the size, shape, and 

 structure of these tentacles of the so-called female Polyps, that 

 they serve a different purpose from those of the terminal Polyps, 

 which are organs of prehension. They seem to be generally 

 immovable, although they may be seen occasionally unfolding or 

 contracting themselves. No satisfactory explanation had yet 

 been given of the use of these tentacles, when it was suggested 

 by Dr. Cabot, that they might be connected with the process of 

 fecundation, in giving passage through the opening which they 

 surround, to the Spermatozoids or animal pollen; thus we might 

 explain in a satisfactory way, why it is that the disappearance 

 of the germinative vesicle and the furrowing of the yolk, which 

 are the surest indications of a beginning development, take place 

 only when the bags have been pushed out of the cell and have 

 thus come within the reach of the Spermatozoids. 



This suggestion induced M. Desor to look more closely at the for- 

 mation of these tentacles ; since viewed in that light, they involved 

 the very important question of a determined sexuality in these 

 lower animals. Spermatozoids were said to have been seen by 

 M. Krohn in the Campanularia. But this observation was 

 doubted and contradicted by M. Van Beneden. M. Desor had 

 never seen any true Spermatozoids, but he now remembered having 

 noticed the last year similar tentacles on the top of cluster-like 

 sacs, where no ova could be discovered. The same was found 

 again this year. He noticed further in the interior of these bags a 

 fine granular structure. On compressing them slightly, he saw 

 these fine granules escaping from the cavity between the tenta- 

 cles, and recognized them distinctly as Spermatozoids. But at 

 an earlier period, before the Spermatozoids are ripe, the bags 

 that contain them are hardly to be distinguished from the female 

 bags containing eggs. An opening surrounded by tentacles, 

 similar to that by which the Spermatozoids escape in the male 

 cells or seminal sacs, serves for their reception in the female 

 ovarian sac, and there is therefore some reason to suppose that 



