CHARACE^l. 65 



power of growth ; their terminal cell, too, is not enclosed by a 

 cortex. Leaflets are borne at their nodes. The growth of the 

 stem is unlimited, and proceeds by means of an apical cell (Fig. 

 62 .s). The apical cell divides into a segment-cell and a new 

 apical cell. The segment-cell then divides by a tivmsverse wall 

 into two cells, one lying above the other ; the lower one, without 



FIG. 61. Cltarafrajilis. A Portion of a plant, natural size. B Portion of a leaf b, with 

 'leaflets j3'-|3" ; a antherldiiim ; c oogonium. C A shield. Nitella flexilis. D Filament from 

 antheridium with sperm itozoids. E Free spermatozoid!". 



Any further division, becomes one of the long, cylindrical, inter- 

 nodal cells (Fig. 62 m), and the upper one (Fig. 62 n) divides 

 by vertical walls to form the nodal cells. The cortical cells 

 (Fig. 62 r) which surround the long internodal cells of Chara, are 

 derived from the divisions of the nodal cells ; the cells covering 

 'the upper portion of an internodal cell being derived from the 



