20 BOTANY OF THE LIVING PLANT 



1. 11, HI. 



IV. 



VII. 



/" 



V. 



\'III. 



TX. 



I'IG. II. 



I. -IX. Successive stages, drawn from different Individual cells of the same root 

 oiAUiitntcepahyDt. J. M. Thompson (x 730). They illustrate the steps in the pro- 

 cess of division of a vegetative cell. Such division accounts for the normal increase in 

 number of cells in the " soma," or plant-body : it is therefore called somatic division. 

 Details of behaviour of the nucleus in division will be given later (Chapter -xxxi.). 



The division of the cell being constantly as described, it follows 

 that every cell arises from a pre-existent cell, and every nucleus :s 

 derived from a pre-existent nucleus, by division. The plastids also 



