in the Interior of Cells. 3 



that it furnishes the material both for the formation of the nu- 

 cleus and of the primordial utricle, which stand not only in the 

 nearest relation as to space, but react towards iodine in an ana- 

 logous manner, consequently that their organization is the pro- 

 cess which induces the formation of the new cell, I trust it will be 

 considered justifiable if I propose to designate this substance by 

 the word protoplasma, a term which recalls to mind its physiolo- 

 gical function*. 



With respect to the relative position of the protoplasma to the 

 nucleus, the form of the latter, and its position with reference to 

 the wall of the cell, I cannot quite agree with my friend Schleiden. 

 According to his statement (Grundz. d. wiss. bot. 2nd edit. i. 

 p. 198), the nucleus represents a plano-convex, generally len- 

 ticular body, which is applied to the inner wall of the cell, fre- 

 quently adhering firmly to it, and in many cases being even in- 

 closed by a doubling of the cell-wall. I must, from my inves- 

 tigations, take a different view of the relation of the nucleus to 

 the cell-wall. In my paper on the structure of the vegetable cell 

 I have already mentioned that the nucleus is not immediately 

 applied to the cell-wall, but is situated within the primordial 

 utricle, either resting against one of its side-walls or being sus- 

 pended by filaments in its centre. My recent researches have 

 shown me that the apposition of the nucleus to the side of the 

 cell is a secondary state under all circumstances, and that in 

 the earliest stage of the cell the nucleus is always situated in its 

 centre, surrounded by a layer of protoplasma. I have on a 

 former occasion f described the remarkable changes in position 

 of the nucleus in the mother-cells and spores of Anthoceros Icevis, 

 and I have found that this relation is very general. That the 

 position of the nucleus is originally central may most readily be 

 observed by the examination of young hairs ; for here, when they 

 are turned round their axis, not the least doubt can exist as to 

 the central position of the nucleus ; for instance, in the hairs of 

 the filaments of Tradescantia virginica, T. Sellowiana ; in the hairs 

 on the young leaves of Saxifraga decipiens, &c. ; and likewise in 

 cells which lie together in masses, for instance, in the cells of 

 the albumen of Paonia, of Leguminosce, in the young vascular 

 utricles of monocotyledonous roots ; in short, I arrived at the 

 same result wherever I examined young cells. The space be- 

 tween the nucleus and the cell- wall is, in most cases, somewhat 

 narrow in the young cell, the nucleus occupying at first a very 



* The author objects to the term mucilage, employed by Schleiden to 

 designate this substance, as the term vegetable mucilage, in the sense in 

 which it is ordinarily used in chemical works, conveys a totally different 

 meaning. 



t On the development of the spores of Anthoceros l<cvis, Linnrca, 1839, 



B2 



