PHYSIOLOGICAL BOTANY. 229 



gations it would be very desirable that the objects should 

 be carefully distinguished. What applies to the Algae 

 cannot necessarily be assumed as holding good in the 

 case of the Phanerogainia, and still less, what is observed 

 in Fungi, as the author has done. His observations upon 

 the cells of the ripe and unripe berries of Solatium nigrum 

 are valuable, but this is a distinct subject, and one which 

 may be of importance as regards the ripening of the 

 fruit, and it would have been very desirable for the 

 author to have instituted a minute comparison in this 

 point of view. Again, the title, ' The Life of the Vege- 

 table Cell/ says too much. My friend Hartig knows as 

 much of the life of the cell as I do, i. e. nothing. Life 

 is motion, arising from internal excitation, and we are 

 unacquainted with the movements of the fluids in the 

 cell which produce development. 



Schleiden says, in his ' Principles of Scientific Botany/ 

 p. 200 : " I believe that even in the youngest condition 

 of the cell, a delicate membrane and a substance which 

 is not colorable by iodine may be distinguished; the 

 former of which completely incloses the cytoblasts. 

 Mohl has apparently (Bot. Zeit., 1844, No. 15 et seq.) 

 misunderstood me, in relying upon an expression which 

 was certainly ill-chosen by me, and by which I intended to 

 illustrate this point, when I first published my discoveries. 

 But as soon as this primary membrane of the cell has 

 become even slightly separated from the cytoblast by its 

 expansion, the whole of its inner surface is very frequently 

 found covered with a delicate coating of semifluid (very 

 often circulating in reticularly-anastomosing currents) mu- 

 cilage, which is sometimes granular, sometimes perfectly 

 homogeneous and pellucid, but may always be rendered 

 visible either by nitric acid, alcohol, or iodine; this is Mohl's 

 primordial utricle." The granulo-cellular mass, called 

 the cytoblast, certainly always appears surrounded by a 

 delicate membrane. At first this mass appears compact, 

 but subsequently it becomes divided, alid then the motion 

 of the small granules begins to be visible. In the cells 



