and its Nucleus in Chara verticillata. 27 



small, so small indeed that they are but granules in size, com- 

 pared with the nuclei of the plant and root-cells, — it does not 

 seem far-fetched to assume that the nucleus is an organ of 

 generation. 



Further, should it hereafter be proved that the rhizopodous 

 cells are developments of Chara itself, and not a foreign organism, 

 it might not be found difficult to trace a connexion between the 

 so-called "gonidia^^ and the "spiral filaments." Thus Chara, 

 in some forms, would then be an animal, and in others a vege- 

 table, according to the distinction between it and Amoeba, which 

 will presently be mentioned ; for the rhizopodous cells do not 

 produce the " gonidia " or monads until they have enclosed a 

 portion of the cell-contents, after the manner of Amoeba when 

 taking its food. Again, I have already shown how the nucleus 

 of the latter divides up into granules and cells producing new 

 beings, and how it becomes lost in the development of the 

 ovules*, and Stein has shown that the nucleus of Vorticella be- 

 comes divided up into cells to produce a new litter ; also, that it 

 shrinks into a small elliptical effete mass of fine granules in the 

 development oiAcineta through the Acineta-f orm, which I have 

 frequently been able to confirm. So that, if the nucleus in 

 Amoeba and Vorticella be identical with that of Chara, we shall 

 probably not be far wrong in assigning a generative power to it 

 generally ; that is, through duplication in common reproduction 

 and by multiple division in the true process of generation. We 

 must therefore, if we adopt these views, regard the nucleus of 

 the ff lobule as merely a modification of that of the cells of Chara 

 generally, to meet the requirements of the case ; and hence as a 

 subordinate organ, which, together with the other parts of the 

 protoplasm, is subject to a common developmental power. It 

 has already been stated, that the nucleus perishes as soon as its 

 functions cease, while the cell to which it belonged goes on 

 growing. Thus the internode of the large Nitella of Bombay f, 

 which may be half a foot long, loses its nucleus, probably 

 when, as a cell, it does not exceed the 100th part of an inch, 

 for the nucleus disappears long before the layer of green- cells is 

 formed. 



It has not, however, been shown what becomes of the small 

 nucleoli of the efiete nucleus ; and perhaps it would be as well, not 

 to assume that no more new cells can be formed after this takes 

 place ; for, if the cortical layer of cells is ever added to the first 

 internodes and branches of the young plant of Chara verticillata, 

 which I have already stated to commence in the simple form of 

 Nitella, it must be some time after the nucleus has ceased to 



* Ann. and Mag. Nat. Hist. vol. xviii. p. 222. 

 t Idem, vol. xvii. p. \02, foot-note. 



