276 THE PHENOMENON OF 



observed by Hofmeister in the embryo-sac of Funkia 

 cmrulea* and described in the following manner. About 

 the time of the opening of the flower, before fertilisation, 

 but after the germinal vesicles have been formed, a new cell 

 is formed around the still existing primary nucleus of the 

 embryo-sac, which cell only occupies a small portion of the 

 internal cavity of the embryo-sac, in its lower third. After 

 the formation of this cell the original nucleus becomes dis- 

 solved, and two or more imcleus-like structures appear 

 in its place in the daughter-cell, but no further cells seem 

 to be formed around them. The formation of this central 

 daughter-cell belongs to the many structures occurring 

 in the embryo-sac which vanish again very quickly. The 

 same observer describes a similar process in the endo- 

 sperm-cells of Ornitlwgalum S'ulphureum,\ in which, after 

 they have become parenchymatously connected, a new 

 daughter-cell Jiot filling up the mother-cell is likewise 

 formed around the still present primary nucleus, which cell 

 sometimes becomes doubled by division, and around which 

 still other free cells appear subsequently to be formed. 



b. Several free dauffhter-cells are formed around newly- 

 formed nuclei.\ — The nucleus of the mother-cell fre- 

 quently survives during the formation of free daughter- 

 cells of this kind, indicating persistent vitality in the 

 conteiits of the mother-cell by the mucilaginous radii 

 proceeding from it. The number of daughter-cells 

 appears never to be accurately defined. All the cases 

 referable here occur in the embryo-sac of the Phanero- 

 gamia, in fact, it is doubtful whether anything similar 

 occurs anywhere else in the development of plants. We 

 have to examine : 



a. The formation of germinal vesicles The embryo- 

 sac, or germ-sac, as it is termed, is the last cell of the 



* Hofmeister, ' Die Bnstehung cles Bmbr. der Phanerog./ p. 13, t. viii, 

 f. 8, 9, 10. A similar phenomenon is described in Asphodelus luteus, p. 10. 



t L. 0., p. 14, t. xiv, f. 17—19. 



X Hofmeister, 1, c, p. 11, is especially to be consulted regarding the 

 origin of the nuclei themselves. 



