STEMS. 99 



it may remain short, in which case the expanded leaves 

 form a cluster or rosette, as in Dandelion. The tender 

 leaves of the bud are not uncommonly protected from the 

 weather by coverings in the form of tough scales, with the 

 additional safeguard sometimes of a wax-like coating on 

 the surface of the latter, as seen in the conspicuous buds 

 of the Horse-Chestnut, and the cap-like coverings of those 

 of the Spruce. 



138. Between the cotyledons of the Bean (Fig. 81), at 

 the top of the radicle, we found a minute bud called the 

 plumule. Out of this bud the first bit of stem is developed 

 (leaving out of consideration the radicle itself), and during 

 the subsequent growth of the plant, wherever a branch is 

 to be formed or a main stem to be prolonged, there a bud 

 will invariably be found. The branch buds are always in 

 the axils of leaves, and so are called axillary, and it not 

 uncommonly happens that several buds are found together 

 in this situation. 



139. Adventitious buds, however, are sometimes produced 

 in plants like the Willow, particularly if the stem has 

 been wounded. As already mentioned, they are also 

 occasionally produced upon roots, as, for example, upon 

 those of the Poplars. 



140. The bud from which the main stem is developed, 

 or a branch continued, is of course at the end of the stem 

 or branch, and so is terminal. 



141. Branching or Ramification. By a branch 



is meant an off-shoot similar in structure to the member 

 from which it springs. Hence the side-shoots of roots 

 are root-branches ; so, also, the lateral out-growths of the 

 stem which resemble the stem itself in structure are 



