16 GENERAL PEINCIPLES. 



tious or accidental^ when originating accidentally as it 

 were, or without any regularity, on the older parts of trees, 



Fig. Ift — Lateral Branch. 

 Fig. 19. Jl, a superior bud. Ji, inferior. C, terminal. A and B, axillary. 



and unaccompanied by a leaf. They are often produced 

 by the breaking or cutting off a branch, or by a wound 

 or incision made in the bark. In the management of 

 trained trees special means are taken to produce these 

 buds on spaces of the trunk that it is desirable to fill up. 

 We sometimes see instances of such buds on the stumps 

 of old trees. 



The teraiinal and axillary buds produced on young 

 shoots, seem to have a different origin from these acci- 

 dental buds — ^the former are connected with the pith of 

 the shoot, as we may see by dissecting them. On cutting 

 into a young shoot below a bud we find a cylinder of pith 

 entering into the bud from the pith of the shoot, but 

 we do not find this connection existing in the case of the 

 adventitious buds. 



Practically considered, buds are classified as follows : — 



1. Lateral. — Those on the sides or circumference of 



shoots, being the axillary buds of the botanist {A^ B^ 

 19).^ 



2. Terminal. — ^Those on the points of shoots ((7, fig. 19). 



3. Sujperior. — Those on the upper sides of horizontal 



branches (J., fig. 19). 



