822 



l^ranclies. But in cuttings the moist medium, in which the cut surface is 

 placed, acts as a modifier. A difference should also be determined accord- 

 ing to whether the branch furnishing the cutting was already in a woody 

 condition, or was still herbaceous. Instead of extensive analyses, we will 

 give here illustrations of an herbaceous Fuchsia cutting and a woody rose 

 cutting. 



The basal part of the Fuchsia cutting (Fig. 197) is shown in longi- 

 tudinal section ; j to j indicates the original cut surface ; the elements appear- 

 ing below this line were formed after the cutting was made; above it {s to s) 

 lie the original tissues, only one-half of which have been shown, m is the 



lip /f'0^ 



Fi«-. 197. Fuchsia cutting-. 



pith ; //, the wood, r, the bark, in which extend the phloem fibres {b). These 

 as well as a part of the wood cells {h') have browned on the cut surface and 

 died. The outer bark (r) also has dried up in the region of the cut surface. 

 The younger, inner bark layers, on the contrary, and especially the pith, 

 have healed over the wound surface by an abundant cell increase. The 

 outer part of this cicatrization tissue is turned to cork and this cork layer 

 {k) has grown to a considerable size through the activity of the cork cam- 

 bium {kc), which forms the protection for the more tender, inner bark 

 tissue. In the callus bark we find the broadened pouch cells (0), with 

 calcium oxalate in raphides. Near these are isolated cell 'groups, with 

 thicker walls (//), which represent the phloem of the vascular bundles 



