AxN ATOMY OF STEMS 



225 



\woocf ray 



simple p/t 



Fig. 59. Radial section of a small portion of the wood of white pine {Pinus strobus). 

 The vertically oriented elongated elements are tracheids. Bordered pits show in face 

 view in the tracheids; in sectional view in marginal ray cells. Simple pits show in 

 surface and sectional views in the ray cells. Half-bordered pits show between marginal 

 ray cells and other ray cells. Three rows of marginal ray cells show in outline only. 



