94 STRUCTURAL BOTANY 



ever, the cambium has short, square-ended cells ; and 

 when a new secondary ray is to be started, the 

 cambial cells first divide up by transverse walls ; so 

 that in this case the form of the cambial cells is 



Fia. 36. Part of a radial section through the secondary 

 wood of Wallflower, p, xylera-parenchyma ; v, vessel ; 

 /, fibrous cell ; mr, medullary ray. The arrows M and 

 G point respectively towards pith and cortex. Magnified 

 220. (R. S.) 



similar to that of the elements which they produce. 

 This, however, does not always hold good, for the 

 vessels and fibres of the wood undergo considerable 



