BUDS. 51 



part increases and becomes the apex of the bud, and by a lon- 

 gitudinal section of the bud and stem at this stage, the rudi. 

 ment of a branch may be distinctly traced under iho micro- 

 scope; the prccnis.li mciiullary sheath and pith being separa- 

 ted by a wiiite deposit from the greenish portion, whicii is to 

 become the bark. There is a bud on the extremity of the 

 branch called the termirul hud, similarly constituted to the 

 axilary ones above descril)ed. The scales, by wiiich the rudi- 

 mentary branch is enclosed, appear to l)e formed for this express 

 purpose, but they are indurated, partially developed leaves, 

 as one may readily convince himself by taking in the spring 

 the bud of the Buckeye, and he will find the outer scale hard, 

 drv, and with a uniform mariiin, but by removinc: one at'ter 

 another he will ^n{\ them gradually becoming soft, delicate, and 

 lobed, being the miniature leaves of the plant. The leaves 

 first developed arc sacrificed for the protection of the re.nain. 

 der during the cold of winter. Plants of the torrid zone and 

 annuals have no such covering, as from tlie nature of the case 

 they need none. The one growing in a climate where the 

 cold of winter is not felt, the other existing only througli a 

 period favorable for vegetation. The buds arc not only en- 

 closed in scales, but they are often provided with means which 

 render their covering much more effectual in resisting out- 

 ward intluences. A resin is not unfrcquently secreted by 

 which the scales arc attached to each other, and rendered 

 proof against the action of water, as in the Balm of Gilead, 

 and Poplars, virc. In others a coating of soft down is produ- 

 ced on the surface of the scales, which affords an addition- 

 al protection in the colds of winter, as in the Willow, and ma- 

 ny others. 



56. Buds, wo remarked, were the rudiments of branches, 

 but it sometimes happens from some cause that these branch, 

 es are not developed at all ; at others, thev are only partly 

 developed, receiving a check in their growth, and becoming 

 thorns and spines. The student may readily convince him- 

 self of the fact, that thorns are partially developed branches, 

 by observing almost any thorny bush at different times. The 

 Plumb often presents striking examples of it, on which the 

 student may find the branch in every state of development, 

 and the thorn of one year may receive an additional impulse 

 the next, and become a branch. 



57. Since the development of buds produces branches, it is 

 plain that the arrangement of branches will be the same as 

 that of buds; and as buds have their origin at the base of 

 learw, it is equally plain, that the branches of trees follow 



