LESSON 4.] GROWTH OP PLANTS FEOM BUDS. 



21 



An annual herb flowers in the first year, and dies, root and all, 

 after ripening its seed : Mustard, Peppergrass, Buckwheat, &c., are 

 examples. 



A biennial herb — such as the Turnip, Carrot, Beet, and Cabbage 

 — grows the first season without blossoming, survives the winter, 

 flowers after that, and dies, root and all, when it has ripened its seed. 



A perennial herb lives and blossoms year after year, but dies 

 down to the ground, or near it, annually, — not, however, quite down 

 to the root : for a portion of the stem, with its buds, still survives ; 

 and from these buds the shoots of the following year arise. 



A Shrub is a perennial plant, with woody stems which continue 

 alive and grow year after year. 



A Tree differs from a shrub only in its greater size. 



42. The Terminal Bud, There are herbs, shrubs, and trees which 

 do not branch, as we have already seen (35) ; but whose stems, 

 even when they live for many years, rise as a simple shaft 

 (Fig. 47). These plants grow by the continued evolution of a bud 

 which crowns the summit of the stem, and which is therefore called 

 the terminal bud. TMs bud is very conspicuous in 

 many branching plants also ; as on all the stems or 

 shoots of Maples (Fig. 53), Horsechestnuts (Fig. 48), 

 or Hickories (Fig. 49), of a year old. When they 

 grow, they merely prolong the shoot or stem on which 

 they rest. On these same shoots, however, other buds 

 are to be seen, regularly arranged down their sides. 

 We find them situated just over broad, flattened places, 

 which are the scars left by the fall of the leaf-stalk the 

 autumn previous. Before the fall of the leaf, they 

 would have been seen to occupy their axils (39) : so 

 they are named 



43. Axillary Buds. They were formed in these trees 

 early in the summer. Occasionally they grow at the 

 time into branches : at least, some of them are pretty 

 sure to do so, in case the growing terminal bud at the 

 end of the shoot is injured or destroyed. Otherwise 

 they lie dormant until the spring. In many trees 

 or shrubs (such for example as the Sumach and Honey-Locust) 

 these axillary buds do not show themselves until spring ; but if 



FIG. 48. Shoot of Horsechestnut, of one year's growth, taken in autumn after the leaveg 

 bave fallen. 



