2(^6 



THALLOPHVTES. 



whorls of leaves of beautiful regularity; their cells are densely filled with starch 

 and other formative materials ; new plants are produced from shoots laterally 

 developed. (2) The Branches ficith naked base of Pringsheim. These are formed 

 on old nodes which have survived the winter or on cut nodes of Chara in the 

 axils not only of the oldest but also of the younger leaves of a whorl, and are in 

 fact only slightly different from the normal branches, the greatest difference being in 

 the partial or entire absence of a cortex on the lower internode and on the first 

 whorl of leaves. The cortical lobes which descend from the first node of the branch 



Fig. 193.— Rhizoids of Chara fraf^ilis ; A end 

 in process of development ; B a 'joint,' the lower 

 part of the upper cell is branching (after Pring- 

 sheim, X 240). The arrows indicate the direction 

 of the currents of protoplasm. 



Fig. igd.— Chara fragilis, A an entire pro-embryonic branch; 

 I the lowermost colourless cell below the root-node; rf root-produc- 

 ing leafless node ; q the long cell proceeding from the middle cell of 

 the bud-rudiment ; pt apex of the pro-embryo ; g the pseudo-whorl 

 of leaves, "v the bud of the leaf-bearing plant ; B upper part of 

 a young pro-embryonic branch ; i, d, q as before, b apex of the 

 pro-embryo ; /, //, /// the young leaflets of the transitional node, 

 V the bud of the leafy stem ; C still younger pro-embryonic branch ; 

 i, d, q, b as before ; /, //, /// the cells out of which the transi- 

 tional nodes arise, v apical cell of the stem-bud (after Pringsheim, 

 B X 170). 



often become detached from the internode and grow free, curling upwards, while the 

 leaves of the lowermost whorl often do not form nodes. (3) The Pro-embryonic 

 Branches. These spring, together with the last, from the nodes of the stem, but 

 are essentially different from the branches, and have a similar structure to the pro- 

 embryos which proceed from the spores. Like the last, they have only been observed 

 in Chara fragilis (by Pringsheim). A cell of the node protrudes and grows into a 

 tube, and its apex becomes separated by a septum. In this growing terminal cell 



