'%\ 



24 



nO\! PLANTS GROW YEAR AFTER YEAR. 



the summit of the preceding one. There are old trees even, which consist of a 

 simple, unbranched stem. Palm-trees, such as our Southern Palmetto (Fig. 79) 



are of this kind. But more commonly, as stems grow they 



multijjly themselves by forming 



53. B.ancheS, or sidc-shooff,-. These are formed both by 

 roots and l)y stems. Roots generally branch much sooner 

 than stems do. See Fig. 4, 20, 30, iV'c. 



54. Roots send off their l)ranchcs from any part of the 

 main root, or start from any part of a stem lying on or in 

 the soil ; and thoy have no particular arrangement. 



55. liut the branches of stems spring only from particular 

 [)laces, and ai-e arranged on a regular plan. Tliey arise from 

 the A.n'! of a leaf and nowhere else, except in some few 

 peculiar cases. The axil (from a Latin word meaning the 

 armpit) of a leaf is the hollow or angle, on the upper side, 

 where the leaf is attached to the stem. As bran(;hes come 

 only from the axils of leaves, and as leaves have a perfectly 

 regular and luiiform arrangement in each particular plant, 

 the places where branches will appear are fixed beforehand 

 by the places of the leaves, and thoy must follow their 

 arrangement. In the axils, commonly one in each, branches 

 first appear in the form of 



56. Buds. A Bud is an undeveloped stem or bi-anch. If 

 large enough to have its parts distinguishal)le, these are seen 

 to be undevelopetj or forming leaves; and large buds which 

 are to stand over winter are generally co\ered with protect- 

 ing scales — a kind of drv, diminished leaves. 



57- Terminal Bud. So t];e plmmile or first shoot of the 



61 embryo (see Fig. 22, S:c.) i.s a bud. But this first bud makes 



the main stem, and its growth, week after week, or year after 



year, carries on the main stem. Palms (as Fig 79) grow in this way by this 



bud only. Being always on the end of the stem, that is, terminating the stem, 



it is called the TcDiiinal Bwh 



58. Axillary Buds. But the buds which ai'e to form branches appear on the 

 sides of the stem ; and since they are situated in the axils of the leaves, as just 



i 



