206 Proceedings of the Royal Physical Society. 



200 nuclei in tubes of Cladophora, many also in Vaiccheria, 

 Empusa, and Infusorians. Hegelmaier* finds multinucleate 

 cells in the suspensor of Dicotyledons ; and Treub,f whose 

 researches are earliest and most elaborate of all, has proved 

 the plurality of nuclei of constant occurrence in the vegeta- 

 tive cells of phanerogams, especially in the laticiferous cells 

 and bast fibres of JEuphorhia, Vinca, etc. All the nuclei in 

 one cell sometimes divide simultaneously, division just stop- 

 ping short of the formation of septa. Considerable light has 

 also been thrown on the multinucleate condition by the 

 recent observations of Macfarlane on the development of 

 Chara. \ He finds that the internodal cells partially keep 

 pace with the division of the nodal cells, their nucleolus first 

 dividing repeatedly, and the multinucleolate nucleus then 

 breaking up into many portions. In the nodal cells the 

 nucleolus also proliferates when division ceases, and the 

 nucleus may break up. 



The multinucleate condition thus loses much of its 

 apparently anomalous character, and seems to be readily 

 assumed by large cells, such as giant cells, in which 

 abundant nutrition continues after maturity. A special 

 term — such as syncytium, proposed by Gegenbaur — seems 

 unnecessary. 



4. The generalisation Omnis cellula e cellulco being ac- 

 cepted, are we also to admit the similar maxim, Omnis 

 nucletis e nucleo ? In the majority of cases this is, of course, 

 true ; but do no exceptions occur — is free nucleus formation 

 in protoplasm impossible ? In this relation, while by no 

 means intending to commit myself unreservedly to the main- 

 tenance of that (on the whole less probable) view, I am 

 desirous of calling the attention of other investigators to two 

 cases already described and figured by myself, which appear 

 decidedly to support it. The first case was observed in a 

 species of Entci^omorpha § (see fig. 2), in which the new cells 



* Journ. Roy, Micro. Sci., 1880, p. 979. 

 + Niedei-land Archiv. , 1879. 

 X Trans. Roy. Soc. Ediii., 1882 



§ On the Plienomen.a of Variegation and Coll Multiplication in a species of 

 Entcromorpha (Trans. Roy. Soc. Edin., 1879-80), 



