34 



BOTANY OF CROP PLANTS 



are similar in appearance, it is quite evident that they are 

 capable of developing into different tissues. Just back of 



r Xylemfroni the procamblun 



Cylem from the procamblum xvlem f rom the cambium 



Xylem from the cambium .phloem from the procamblum and cambium 



rhloem from the procamblum and cambium miuouiiium <= w 



Fig. 15. — Diagram showing the evolution of tissues from the primordial 

 meristem down to the beginning of cambial activity. {After Stevens.) 



the growing point, we note that the cells have differentiated 

 into three main regions: epidermis, ground meristem, and 



