REPRODUCTION OF PLANTS. 103 



or two trees together, each remaining in the 

 ground held by its own roots, and taking off the 

 bark of each at the point of contact ; the liber 

 and pith of the two plants soon unite by the de- 

 velopment of their cambium, and one of them 

 may then be cut away below the junction. The 

 third method is by the insertion of a portion of 

 a stem containing a bud in the axil of a leaf, 

 within the bark of the tree on which we desire 

 to ingraft it; the bud thus inserted receives nou- 

 rishment from the juices of the tree in which it 

 is placed, and is developed as it would have 

 been on the stem from which it was originally 

 taken. 



76. There are various subjects of great inte- 

 rest connected with the reproduction of plants, 

 whether from seed or division, but which are 

 too numerous to be dwelt on in an elementary 

 work : among them is the production of hybrid 

 varieties by fertilizing the stigma of one plant 

 with the pollen from another, which may occur 

 accidentally, if the plants are in each other's 

 neighbourhood, or may be effected at pleasure 

 between those whose natural affinities are very 

 close. In this manner modern gardeners have 

 succeeded in raising numberless varieties of fa- 

 vourite genera. The effect of culture and care 



