74 



ESSENTIALS OF VEGETABLE PHARMACOGNOSY. 



terminate when no such bud is formed, 

 growth continuing until the apical portion 

 is destroyed by an inclement season. In 



rooting at some of its joints, is called a 

 Runner (Fig. 374). A horizontal under- 

 ground stem, fleshy-thickened at least 

 such stems then we have the anomaly of during the first year so as to serve as a 



a perennial stem with an annual tip. 



storage receptacle, and giving origin to an 



As to their order of development in time aerial summit or branch, is a Rhizome 



stems are Primary, Secondary and so on, 

 terms which are self-exnlanatorv. 



(Figs. 368, 369, 371 and 372). The growth 

 and duration of a rhizome may be indefi- 



As to their position and nature of origin nite, like those of stems, as in the case of 



stems are Aerial or Subterranean, which 

 terms are also self-explanatory. A see- 



the rhizome of Podophyllum (Fig. 369), or 

 they may be restrictod to one or to a defi- 



ondary stem assuming an erect position nite number of years, after which the old- 

 from the base of the primary is a Sucker. est existing phytomer perishes each year 



Such a one arising from a rhizome at a 

 considerable distance from the original 

 erect stem is called a Stolon. A short 

 secondary stem developing from the base 

 of the primary is called an OflfseL An 

 elongated, slender one, lying prostrate and 



F-g. ill. 



w 



as a successive apical one is formed (Fig. 

 371). Rhizomes are so numerous and im- 

 portant in pharmacy that their characters 

 call for special attention. They are 

 classed as short or elongated, the former 

 term referring to those the extreme lemrih 



