56 GENERAL PRIKCIPLES. 



they had received their due share of nutriment, fail in 

 attaining the proper condition, and produce only rosettes 

 of leaves. During the unfruitful season, immense quan- 

 tities of fruit-buds are again brought forward, and the 

 year following, the tree is overloaded ; so it proceeds in 

 regular alternation. 



' This is never experienced in trees regularly pruned, and 

 may be remedied by thinning out the crop in bearing 

 years, leaving on but a reasonable amount, that will not 

 exhaust the tree. The bearing years have been complete- 

 ly reversed by removing the blossom-buds, or fruits, on 

 the bearing yeai'. 



Section 7. — The Fruit. 



1st. Character of the Fruit. — As soon as the ovules are 

 impregnated, the ovary begins to swell ; the petals,stamens, 

 and other parts of the flower fall off, and we then say the 

 fruit is "se^." As a fruit-bud is but a transformed leaf-bud, 

 a fruit occupies the same relative connection with the tree 

 as a branch ; it attracts food from the stem and the atmos- 

 phere in the same manner, and performs all tlie same func- 

 tions, except that it does not, like the leaf, return anything 

 to the tree, but appropriates all to its own use ; and this 

 is the reason, as we have before remarked, that trees hav- 

 ing borne a heavy crop of fruit one season, are less fruitful 

 the next — this is the case only with fruits, as the apple 

 and pear, that require nearly the whole season to mature 

 them. Cherries and other fruits, that mature in a shorter 

 period, and that draw more lightly on the juices of the 

 tree, do not produce this exhaustion, and consequently 

 bear year after year uninterruptedly. 



2d. Classification. — In some fruits, as the apple, for in- 

 stance, the fruit appeai-s to be formed below, or at the base 

 of the calyx ; structurally, it is properly regarded as an 

 adhesion of the greater part of the calyx to the ovary ; 



