CLASSIFICATION OF ROOTS AND STEMS. 



4 



8 



Fg.?fel 



f; 



g.3fa7 



Fig. 366 



shaped (Fig. 36G), Capillary when very atic or fleshy elements is so much greater 



thin, long and hair-like. 



than that of the woody that a woody char- 



As to consistency, they are denominated acter is not apparent. In practical phar- 

 macognosy, where dried roots are mostly 



as Woody and Fleshy. By "fleshy" or 

 **non-woody" we do not mean that wood 



observed, a number of other terms, as in 



tissue is entirely lacking, but rather that the case of the bark, come into use. 

 the proportion of the cellular, parenchym- 



CLASSIFICATION OF STEMS, INCLUDING BUDS. 



Stems may be classified as to duration, 

 order of development in time, position and 

 nature of origin, mode of extension, direc- 

 tion of growth and nature of support, 

 modification of form or function and con- 

 sistence. 



As to duration they are, like roots, An- 

 nual, Biennial and Perennial. Annual 

 stems are those which die at the close of 

 the season. They may or may not pertain 

 to annual roots. Plants possessing them 

 are called Herbs. Herbs are therefore 

 either Annual, Biennial or Perennial, in 

 accordance with the character of the root. 

 The definition of an herb is a plant, the 

 aerial portion of the stem of which dies 

 at the season's close. The stem of an 

 herb is denominated Herbaceous. Bien- 

 nial stems are those which are produced, 

 usually underground like that of the po- continued growth the nest season; Inde- 



tato (Fig. 36Tb), during one season, and 

 perish after the production of their 

 branches in the following season. Occa- 

 sionally, however, like the cabbage, a bi- 

 ennial stem is aerial. Fleshy-thickened 

 and biennial portions of underground 

 stems, such as the potato, are denominated 

 Tubers (Fig. 3G7a). Fleshy-thickened 

 basal portions of stems which are in- 

 vested by more or less fleshy-thickened 

 storage leaves are called Bulbs. The va- 

 rieties of the bulb will be considered un- 

 der the subject of buds. Perennial stems 

 are those which live and extend their 

 growth from year to year. They are De- 

 terminate when their growth of the sea- 

 son is self-limited and closes with the pro- 

 duction of a specially prepared Winter- 

 bud, which protects the growing point for 



