scio>s. 171 



347. When, in such instances, the communication between 

 Uie stock and the scion is so much interrupted that the sap can 

 no longer ascend with sufficient rapidity into the branches, 

 the latter die ; as in many Peaches. 



348 This incomplete union between the scion and its stock 

 is owing to some constitutional or organic difference in the two. 



349. Therefore care should be taken that when plants are 

 grafted on one another, their constitution should be as nearly 

 as possible identical. 



350. As adhesion of only an imperfect nature takes place 

 When the scion and stock are, to a certain degree, dissimilar 

 in constitution, so will no adhesion whatever occur when 

 their constitutional differences are very decided. 



351. Hence it is on'y species very nearly allied in nature 

 that can be grafted on each other. 



352. As only similar tissues will unite (19.), it is necessary 

 in applying a scion to the stock, that similar parts should be 

 carefully adapted to each other; as bark to bark, cambium to 

 cambium, and alburnum to alburnum. 



353. The second is more especially requisite, because it is 

 through the cambium that the woody matter sent downwards 

 by the buds must pass; and also because cambium itself, being 

 organising matter in an incipient state, will more readily form 

 an adhesion than any other part, 



354. The same principles apply to buds, which are to scions 

 precisely what eyes (319.) are to cuttings. 



355. Inarching is the same with reference to grafting, that 

 layering (324) is with reference to striking by cuttings. 



356. It serves to maintain the vitality of a scion until it <?an 

 form an adhesion with its stock ; and must be considered the 

 most certain mode of grafting. 



357. It is probable that every species of flowering plant, 

 without exception, may be multiplied by grafting. 



358. Nevertheless, there are many species and even tribes 

 that never have been grafted. 



359. It has been found that in the Vine and the Walnut this 

 difficulty can be overcome by attention to their peculiar con- 

 stitutions; and it is probable that the same attention will 

 remove supposed difficulties in the case of other species. 



XV. Transplantation. 



360. Transplantation consists in removing a plant from the 

 soil in which it is growing to some other soil. 



361. If in the operation the plant is torpid, and its spon- 

 gioles uninjured, the removal will not be productive of any 

 interruption to the previous rate of growth. 



362. And if it is growing, or evergreen, and the spongiole s 

 ire uninjured, the removal will produce no further iniury tha n 



