817 



stance, that in the frn it-flesh of the peachalmond, and as I may add 

 now, also in that of the almond itself, there is a system of gnm 

 canals, precisely corresponding to that of the vascnlar bnndles. Of 

 these the phloem bnndles are converted into gnm canals by cytolysis, 

 either entirely or with the exception of the onter protophloem ; the gum 

 canal (gp Fig. 2 and 3) thns, is always immediately contiguons to 

 the woody bundle xl. 



Fig. 2 (3). Gum canals in the transvei'se 

 section of the fruit-flesh of a peachahnond : 

 ha hairs on epidermis; Aw dermoidal tissue; 

 bp chlorophyll-parenchyma; xl xylem bund- 

 les; ph phloem bundles; gp gum canals 

 sprung from phloem bundles. 



Fig. 2 and 3 are reproductions from my 

 above mentioned treatises of 1883 and 1886. 



The presence of gum in the canals of the fruit is easily shown. 

 In August or September the summit of a peachalmond fruit is cut 

 off and the fruit, or the branch wilh the fruit, is placed in water. 

 After some moments all over the section droplets of gum are seen 

 evidently issuing from the vascular bundles. As these bundles 

 are distributed through the fruit-flesh, running longitudinally and 

 transversely, and are partly reticulated, the number of droplets is 

 very great and they are of different size. In particular near the stone 

 they are big. If in August the gum is allowed to flov/ out in cold 

 water it dissolves completely or nearly so. In September the dissolving 

 is no more complete. By drying the gum, its solubility in cold 

 water gets almost lost, but it continues in hot water. 



From lateral incisions also much gum flows out. In Fig. 1 the 

 drops are represented after drying, followed by swelling up in cold 

 water. 



Although this gum does not only consist of dissolved wall material 



54* 



