BOTANICAL TERMS. 



43 



(c) Roots originate etuloyenotisly, that is to say, they 

 do not develope from the exterior or surface of the plant- 

 body, but always begin in the deeper tissues, and even- 

 tually break their way through the overlying layers till 

 they reach the surface. 



(d) They do not, as a rule, prodvice leaves or buds. 



(e) They tend, as a rule, to grow downwards into the 

 soil, avoiding the light. 



(f) The minute .structure of the root is less perfect in 

 its development than that of the stem. 



The functions of the root are 



(a) To fix the plant in its place. 



(b) To act as an absorbent of the nutritious liquids 

 contained in the soil. 



(c) In special cases to serve as a storehouse of food for 

 the plant. 



B. — Caulome: including the stem and all its equivalents, 

 such as branches, runners, tendrils, thorns, etc., as 

 alreadj^ described. 



In contrast to the root, the stem is always preceded by 

 a bud. 



A bud is an early stage of the development of a stem 

 or branch, and is found on dissection to consist of many 

 rudimentary leaves crowded on a short axis. This axis 

 subsequently developes throughout its length, forming the 

 internodes (Fig. 244), thus differing widely from the root, 

 which grows by additions to its extremity. 



Winter-buds are covered with scaly bracts called bud- 

 scales, which separate and fall away soon after the devel- 

 opment of the bud begins in tlie spring. 



Euds are 



(a) Terminal, when at the ends of stems and 

 branches, 



(b) Axillary, when produced in the axils (Fig. 244) of 

 leaves. 



(c) Adventitious, when produced in some ii-regular 

 manner. 



(d) Accessory, when produced as extra or additional 

 buds beside the regular axillary bud, so that there are 

 really several buds in the axil. 



The functions of the caulome are 



(a) To bear leaves and flowers. 



(b) To serve as a medium for the conveyance of the 

 nourishing liquids absorbed by the root. 



Fip. 244. 



