70S NOTES 



12. Multinucleate, cells. Schmitz : Festschr. Halle, 1893 (Siphonocladiales). 

 Id. Sifczb. niederrhein. Ges. 1879 (Aug.), 1880 (June). Treub : Arch, neerl. 15. 

 Johow : [Jnters. iib. d. Zellkerne in d. Sekretbehaltem u. Parenchymzellen d. 

 hob. Monokot vlcii. [naug. -Dissert. Bonn, 1880. Strasburger : B.Z. 1880. G. Haber- 

 landt : I.e. [8], Ch. 3, VII. (significance of the multinucleate condition). 



13. Functions of nucleus. Nageli : Mechanische Theorie d. Abstammungslehre, 

 Mi'mchen u. Leipzig, 1884, p. 368. Hertwig : Das Problem d. Befruchtung u. der 

 Isotropie d. Eies, Jena, 1885. Strasburger : Neue Unters. iib. d. Befruchtungs- 

 vorgang b. d. Phanerogamen als Grundlage f. eine Theorie d. Zeugung, Jena, 1884. 

 Weismann : Die Kontinuitat d. Keimplasmas als Grundlage einer Theorie d. 

 Vererbung, Jena, 1885. Kolliker : Zeitschr. f. wiss. Zool. 42, 1885. Schmitz : 

 Festschr. Halle, 1879. Klebs : Biol. Centr. 7, 1887. Id. Unters. Tiib. 2, p. 489. 

 G. Haberlandt : I.e. [8]. Id. Sitzb. Wien, 98, 1889 (encysted protoplasts). Palla : 

 Flora, 1890, p. 314, and Ber. 24, 1906 (enucleate protoplasts). Palla, and later 

 Acqua, found that enucleate portions of protoplasm from pollen-tubes, Marchantia- 

 rhizpids and Urtica -hairs remained capable of forming new cell- membranes, so long 

 as the organs from which they were derived showed active growth. It would be 

 a mistake, however, to infer from this fact that cell-wall formation generally takes 

 place independently of nuclear influence. On the contrary, as Palla points out in 

 his first paper, the above-mentioned cases illustrate the after-effects of nuclear con- 

 trol ; presumably, this control depends upon the fact, that the nucleus of the growing 

 cell secretes certain substances which induce the formation of the cell-wall, and 

 that the substances in question are also found in the artificially isolated, enucleate 

 pieces of protoplasm. The mere presence of a reserve-material, capable of conversion 

 into cell-wall-substance, cannot enable enucleate portions of protoplasm to sur- 

 round themselves with a new cell-membrane. Van Wisselingh : Beih. bot. Centr. 

 24, I. 1908 (Spirogyra). Gerassimow : Bull. Mosc. 1890. Acqua : Malpighia, 5, 

 1901. Pfeffer : Ber. sachs. Ges. 1896. Townsend : P.J. 30. Gerassimow : Bull. 

 Mosc. 1896. Id. ibid. 1900. Id. ibid. 1901. Id. Zeitschr. allg. Phys. 1, 1902. Magnus : 

 P.J. 35, 1900 (mycorrhiza of Neottia). Shibata : P.J. 37, 1902 (mycorrhiza). Von 

 Guttenberg : Beitrage z. phys. Anat. d. Pilzgallen, Leipzig, 1905, pp. 22 sqq. Kiister : 

 Flora, 97, 1907. In this paper, Kiister cites a number of cases in support of the 

 author's observations on the position of the nucleus in growing cells. At the same 

 time he claims to have discovered a remarkable exception to the rule ; in a number of 

 water-plants (Hydrocharis morsus-ranae, Trianea bogotensis, Potamogeton lucens, 

 Stratiotes aloides, Vallisneria spiralis, Elodea canadensis, etc.), namely, the nuclei 

 always remain at the proximal ends of the root-hairs. It should, however, be noted, 

 that Kiister has not proved that the root-hairs in question exhibit apical growth, 

 like the hairs of terrestrial roots. It is quite possible that such aquatic root-hairs 

 behave like the trichomes on the stems and petioles of many plants (Geranium 

 sanguineum, etc.), which, as the author has shown, exhibit protracted basal growth, 

 after their apical extension has ceased and accordingly always have their nuclei 

 situated at the base. As regards zoological literature, attention may be specially 

 directed to the papers of Nussbaum, Gruber, Korschelt, R. Hertwig, Hofer, 

 Verworn, etc. 



14. Hacker : I.e. [10], p. 114. The other views regarding the significance of 

 nucleoli are exhaustively dealt with in this paper. Von Derschau : Ber. 22, 1904. 



15. Zacharias : B.Z. 1890. Biitschli : Uber d. Bau. d. Bakterien u. verw. Organis- 

 men, Leipzig, 1890. Palla : P.J. 25, 1893. A. Fischer : Unters. iib. d. Ban d. 

 ( 'vanophyceen u. Bakterien, 1897. Kohl : Organisation u. Physiologie d. Cyano- 

 phyceenzelle, Jena, 1903. Olive : Beih. bot. Centr. 13, 1905. 



