164 CAUSES OF BARRENNESS, &C. 



fore the gems are either carried along another stage in 

 the growth of the shoot or spur containing them, or 

 remain inert in the body of the stem for ever. 



But why, it may he asked, if the fructification be 

 centrally posited as in the bud g, Fig. 47, and ulti- 

 mately displayed on the summit of a similar one on a 

 spur as &tf) Fig. 47, how is it not protruded, as it is 

 natural to suppose it would be, at the first movement 

 of the bursting bud ? To this it may be replied, be- 

 cause the incipient flower is then imperfect, i. e. im- 

 perfect as to bulk, not as to form, and because, at the 

 same time, such is the excitement of the growing 

 principle, that the bases of the buds A, A, Fig. 47, en- 

 veloping the fructification, are elongated forth, carry- 

 ing the gem forward therewith in their apices. We 

 are now alluding to leading shoots, which are seldom 

 fruit-bearers ; but that fructiferous gems are present 

 in the points of even strong leading shoots, we have 

 only to recollect how often we have seen terminal 

 flower buds formed in the autumn on both apple 

 and pear trees as at c, Fig. 47. It appears, 

 therefore, that though the fructiferous gems are in- 

 cipiently present in all cases, it is absolutely necessary 

 to their perfect maturation in the bud, that moderate 

 growth of the tree to allow time for this, and full 

 supplies of air and light are requisite to bring them 

 to perfection. 



There can be no doubt but that the flower bud c, Fig. 

 47, was at the base of the shoot, or in the bud whence 

 it sprung, before its elongation in the previous spring ; 



