FLOWER-LAND. 



which they are joined together in the tissue 



(Figs. 143, 149)- 



And notice also how cells 



change as they grow old and 

 die. There are not only 

 the soft and juicy cells of 

 the yellow orange pulp, or 

 the soft and dry ones of the 

 pith of trees, but sometimes 

 they harden as they dry up 

 so as to form hard tissue* 



like that of bark, or wood, or the stone of a plum 



or peach (Fig. 149). 



Fig. 149. Left hand shows 



bark cells from horse chestnut, 



right hand hard cells from stone 



of damson (sclerenchyma]. 



* cf. sclerenchyma, Appendix. 



