60 



THE LARCH CANKER 



Fig. 26, B, which is an enlarged drawing of the top right- 

 hand corner of fig. 26, A, shows in greater detail the forma- 

 tion of this new cork layer ; PH is here the normal phellogen 

 or cork cambium which makes cork on its outside. The 



B 



FIG. 26, A and B. Cork layer across base of branch. 



see text. 



For description, 



new cork is formed by a new phellogen ph, which is 

 developed right across the cortex and phloem, and makes 

 a downward turn as it approaches the cambium. It is in 

 direct continuation with the outer phellogen at E, and 

 forms, as it were, a side branch of this phellogen. It passes 

 usually transversely across the cortex and phloem (it may 

 be oblique) until it reaches the layer outside the cambium, 



