466 



SECONDARY CHANGES. 



increase extends to all the diameters, so that the general form remains, if not exactly, 

 yet approximately, the same. 



The structure of the cambial cells is given in its most important points, by the 



Fig, soo. 





Fiff- 199. ^. 



Fig. 201, 



Fi//,fTl^„^TSrdi„rstlLtlra°'L .iuring thewinte;. res.. b=^„„i„, of March W 



wood ; r loedcllarj- rays-Fig aoo. Radial tagitudtofslction SI tj ^ ^'^""dary growth, bordering directly ou the mature 

 secondary growth • the latter has rows of Lnd StrfehLrwhh tof 'dart ,„ H° "1 ' '' '^^ ""''"."B,'>y=' """==■> '"= »"d the yomg 

 right into the inner zones of the bast j r medulliO rav F <r ,„, X ''°' ?" ""^ "''"" '='='^ ™"* »°<' P'""^ "«' ™ "" 



shadea;.^,in,it between this and the you^g'se^da'S'gr^fl.^^LXro'nSea^iV.t;?^^^^^^^^ 



Statement of their meristematic properties. They are furnished with densely granular pro- 

 toplasm, and with a well-defined nucleus, which is spindle-shap^, and in the elongated 



