KIXDS OF STEMS AND BKAXCHES. 37 



§ 2. Of Stems. 



90. Forms or Kinds of Stems. Differences in the size and consistence of Ftcm?, 

 such as distinguish plants into herbs, shrubs, and trees, have ah-eady been noticed, 

 in paragraphs G4, Go, and GQ. A stem is 



Herbaceous, when it belongs to an herb, that is, has very little v/ood in its com- 

 position, and does not live over winter above ground: 



SJirubby, when it belongs to a shrub, or is woody : 



Arboreous or Arborescent, wdien the plant is a tree, or like a tree ; that is, when 

 it is tall and grows by a single trunh. 



91. The peculiar straw-stem of a grass or grain is named a Culm. It is gen- 

 erally hollow, except at the joints, which are hard and solid; but in Indian Corn, 

 Sugar- Cane, and some other Grasses, it is not at all hollow. 



92. A? to the mode of growth or the direction it takes in growing, the stem 13 

 Erect or Upright, when it grows directly upwards, or nearly so : 

 Ascenain^, when it rises upwards at first in a slanting direction: 



Declined or Recihicd, when turned or bent over to one side : 



Decumbent, when the lower part reclines on the ground, as if too weak to staiul, 

 but the end turns upwards mere or less: 



Procumbent or TrailinCf, when the whole stem trails along the ground : 



Prostrate, when it naturnlly lies flat on the ground : 



Creeping or Runnina, ^vfhen a trailing or prostrate stem strikes root along it3 

 lower side, where it rests on the ground : 



Climbing, where it rises by laying hold of other objects for support ; either bjr 

 tendrils, as in the Pea, Gourd, and Grape-Vine ; or by twisting its leafstalks around 

 the sup{)orting bodj', as in the Virgin's Bower ; or by rootlets acting as holdfiists, as 

 in the Ivy and Trumpet-Creeper (86) : 



Twining, wdien stems rise by coiling themselves spirally around any support, ua 

 in the Morning-Glory (Fig. 4), Hop, and Bean. 



93. Several sorts of branches are different enough from the comm.on to have 

 particular names. Indeed, some are so different, that they would not be taken for 

 branches without considerable study. Such, for instance, as 



9 L Tliarns or Spines. Most of these are imperfect, leafless, hardened, stunted 

 branches, tapering to a point. That they are branches is evident in the Hawthorn 

 and similar trees, from their arising from the axil of leaves, as branches do. And 

 on Pear-trees and Plum-trees many shoots may be found which begin as a leaf/ 



