SCIONS, 



75 



parts sliould be carefully adapted to each other ; 

 as bark to bark, cambium to cambium, and al- 

 burnum to alburnum. 



The second is more especially requisite, be- 

 cause it is through the cambium that the woody 

 matter sent downwards by the buds must pass ', 

 and also because cambium itself, being organ- 

 ising matter in an incipient state, will more 

 readily form an adhesion than any other part. 

 The same principles apply to huds^ which are 

 to scions precisely what eyes are to cuttings. 



Inarching is the same with reference to 

 grafting that layering is with reference to 

 striking by cuttings. 



It serves to maintain the vitality of a scion 

 until it can form an adhesion with its stock; 

 and must be considered the most certain mode 

 of grafting. 



It is probable that every species of flowering 

 plant, without exception, may be multiplied by 

 grafting. 



Nevertheless, there are many species and 

 even tribes that never have been grafted. 



It has been found that in the Vine and the 

 Walnut this difficulty can be overcome by atten- 

 tion to their peculiar constitutions ; and it is 

 probable that the same attention will remove 

 supposed difficulties in the case of other species. 



