M. Miiller on the Development of Chara. 259 



are formed within it, whence it acquires as many subdivisions, 

 parts or cells (fig. 6). These subdivisions are at first of equal 

 length ; but as they continue progressively to be developed, the 

 lowermost takes the lead and becomes more elongated. The 

 lower ones are then usually the most transparent ; the green con- 

 tents of the cells are more developed in the upper ones, although 

 they are subsequently formed also in the former, seldom however 

 to the same extent. The elongation of the stem now proceeds 

 simply in the same manner, until finally new cells, the whorl of 

 branches, are likewise formed from its subdivisions. These are 

 either developed, as is usually the case, in the earlier stage of the 

 development of the stem on one side only, or subsequently in a 

 comflMe whorl. Moreover new cells, i. e. shoots, are formed from 

 their joints according to the same laws as from the stem, for there 

 can be no question here of any development of leaf. 



As soon as the stem contains a few cells in its interior, a re- 

 markably higher development ensues from its lowermost subdivi- 

 sions. The whorls do not stop short at the formation of shoots 

 as in the upper portions, but are developed into new plants 

 (figs. 6, 7, 8 and 10). This formation is a perfect repetition of 

 the development of the nucleary membrane. As in it, the knotty*, 

 looking cells at the joints (fig. 7) elongate in a sacciform manner 

 (fig. 8), their apices at the same time becoming enlarged (fig. 10) ; 

 these again form new cells in their interior ; the lowest appear 

 more transparent, whilst in the uppermost the green cellular 

 contents are formed. At the base of the axis, close above the 

 orifice of the spore, a similar cell-formation has occurred. For 

 as soon as the nucleary membrane began to burst through the 

 sporular membrane like a bladder and to expand it in a sacciform 

 manner, it began to be developed in a sacciform manner on the 

 opposite side (figs. 4 and 6). Thus the spore, which is at first 

 perpendicular, acquires a horizontal position. Each utricle forms 

 a rootlet, and others follow it from simple vesicular expansion of 

 the nucleary membrane, so that it acquires, at this end, a com- 

 plete head of root-fibrils. 



The question now is — how are all these cells formed ? The 

 direct answer is — by cytohlasts and by these alone. I have not 

 been able to observe this so distinctly in the earliest cells of the 

 stem, although there can be no doubt about it, because there is 

 not the least appearance of a secondary membrane, which might 

 perhaps have become contracted by the well-known process of 

 division, and thus formed new cells. But in the formation of 

 the branches and of the new plants from them, the whole pro- 

 cess may be traced most unequivocally. 



The cytoblastema,or the above-described liquid which is formed 

 from the starch, possesses the remarkable peculiarity that it is 



