156 OBSEIIVATIONS Ox\ INVERTED GROWTH. 



Tlie braiicli that has struck is at present about an inch in 

 diameter nearest tiie ground, then it diminishes in thickness 

 gradually till it becomes about one -fourth of an inch in diameter, 

 when it again increases like other branches the nearer it gets to 

 the main stem of the plant. In this case, if not in reality, we 

 have the appearance at least of part of an inverted branch grow- 

 ing with as much vigour as others that are not inverted, and also 

 connected together. Will tiie sap in tlie bark take opposite direc- 

 tions where the stem is smallest ? If such is the case we must 

 conclude " that the organization of the internal bark becomes 

 again inverted and ada|)ted to the position of the branch." 



I may also notice, that in coimection with the same plant there 

 are other bi-anches that have struck root, and yet scarcely any 

 increase has taken place in their thickness near the ground, 

 altliough several young shoots have sprung up where the branches 

 first struck root in the soil. This may also be accounted for: in 

 the first case the branch that has struck root and increased in 

 diameter near the ground is well feathered, upon small shoots, 

 with living buds, which will in due time produce leaves, and the 

 leaves new wood ; the other branches tiiat have struck root are 

 witliuut buds where the other has them, and where these are 

 wanting there will be no leaves to produce new wood. 



Perhaps tlie same reasoning that Knight applied to his in- 

 verted cuttings may be used in the case of the inverted branch. 

 " The force of gravitation will, however, still be felt, and by its 

 agency sufficient matter to form new roots may be conveyed to 

 those parts of the inverted cutting or tree which are beneath the 

 soil. Besides, if we suppose a variation to exist in the powers or 

 organization of the vessels which carry the sap towards the root, 

 we may also attribute in a great measure to this cause the dif- 

 ferent forms which different species or varieties of trees assume ; 

 for if the fluid in tliese vessels be impelled with much force 

 towards the roots, little matter will probably be deposited in tlie 

 branches, which in consequesice will be slender and feeble, and 

 there is not any tree that has been the subject of my experiments 

 in which new wood accumulated so rapidly at the upper end of 

 inverted plants." 



The growing of inverted plants may be useful in some depart- 

 ments of gardening, especially where plants are wanted to occupy 

 a small space ; for although some plants will grow freely in that 

 position, others will form dwarfish habits, and some species that 

 will not strike from inverted cuttings may succeed when layering 

 is employed. 



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