t 



96 ORGANOGRAPHY. 



From the above circumstances it follows that a bud resembles 

 in its functions the embryo from which growth first commenced, 

 and it has accordingly been termed o, fixed embryo. There is this 

 difference, however, between them : — a bud continues the in- 

 dividual, while the embryo continues the species. A stem is 

 therefore really made up of a number of similar parts or buds, 

 called phytons, which are developed in succession, one upon the 

 summit of the other. Hence, by the development of terminal 

 buds the stem increases in height ; and by those situated late- 

 rally branches are produced. A tree may thus be considered as 

 a compound body, formed of a series of individuals which mu- 

 tually assist each other, and benefit the whole mass to which 

 they belong. In exogenous trees, which form lateral or axillary 

 buds, the destruction of a few branches is of no consequence, 

 as they are soon replaced ; but in Palms, and most other en- 

 dogenous trees, and also in those of acrogenous growth which 

 develop only from terminal buds, the destruction of these under 

 ordinary circumstances, as we have seen, leads to their death. 



The buds or similar parts, of which a tree has thus been shown 

 to be made up, being thus distinct individuals, as it were, in 

 themselves, are also capable of being separated from their pa- 

 rents and attached to other individuals of the same, or even of 

 nearly allied species. The operations of Budding, Grafting, 

 &c., depend for their success upon this circumstance. In some 

 plants, buds naturally separate from their parents, and produce 

 new individuals. These operations are of great importance in 

 horticulture, because all plants raised by such means propagate 

 the individual peculiarities of their parents, which is not the 

 case vtdth those raised from seed, which have merely a specific 

 identity. 



Eamification. — In the same way as branches are produced 

 from buds placed on the primary axis or stem, so in like manner 

 from the axils of the leaves of these branches other buds and 

 branches are formed ; these again will form a third series, to 

 which will succeed a fourth, fifth, &c. The main divisions of 

 the primary axis or stem are called branches {rami), while the 

 smaller divisions of these are commonly termed twigs (ramuli). 

 The general arrangement and modifications to which these are 

 liable are commonly described under the name of ramification. 



All lateral or axillary buds are called regular or normal, and 

 their arrangement in such cases is necessarily the same as that 

 of the leaA-es. Again, as branches are formed from buds thus 

 placed, it should follow that their arrangement should also corre- 

 spond to that of the leaves. This corresponding symmetry, how- 

 ever, between the arrangement of the branches and leaves is 

 interfered with from various causes. In the first place, espe- 

 cially, by many of the regular buds not being developed. Secondly, 

 by the development of other buds which arise irregularly at 



