456 



Messrs. Farmer and Moore and Miss Digby. [Mar. 24, 



tion through which a strand of cytoplasm was still visible connecting 

 the two cells. 



When the migrating nucleus has passed into the neighbouring cell 

 it sometimes fuses at once with the nucleus already present there, 

 but often the two nuclei remain more or less separated for an 

 appreciable interval of time. 



It appears then to be clear that the presence of the pair of nuclei 

 is not to be regarded in these cases as resulting from a division of the 



Fig. 4. 



nucleus proper to the containing cell, but has merely been arrested 

 at a stage short of producing a wall. Such a state of things is very 

 common in the tissue-cells of many plants, but we think that the 

 facts enumerated above suffice to prove that no such simple explana- 

 tion will fit in the present case. 



The migration of the nucleus, as above described, goes on discon- 

 tinuously in a growing apogamous prothalJiun. In this way there is 

 provided a cellular aggregate that may possess no very homogeneous 

 character, nor can one cell, or even isolated groups of cells, be 

 defined as the sole parent tissue from whence the apogamous out- 

 growth may have sprung. And this is quite in harmony with the 



