4 VEGETABLE PHYSIOLOGY. [LESSON 2. 



of delicate, hairlike processes, in constant vibration, will be seen 

 against the light, surrounding the outer margin of the globe (c) ; 

 once clearly seen, they will readily be discovered, arising from the 

 minute dots which cover the external surface (b). By their incessant 

 vibratile action, the rolling motion results, for which these plants are 

 remarkable. 



17. These organs are called cilia, from the Latin word cilium, an 

 eye-lash, which they are supposed most nearly to resemble ; and, from 

 their action, vibratile cilia. These plants are large enough to be 

 seen, when held against the light, by good, unassisted vision. 



LESSON II. 



INTRODUCTION, CONTINUED. 



18. Not only are the perfect forms, or parent plants, seen in 

 incessant motion, but the large green masses (a), so conspicuous 

 in the interior, are also in constant rotation, until, when they have 

 become mature, they desire to effect their liberation and commence 

 an independent existence ; at this period they will be seen to have 

 FlQ 2 numerous small, immature germs in 



their interior, also in motion. 



19. The mode by which they es- 

 cape is by the rupture of the parent 

 cell (Fig. 2) ; here a decided break in 

 the cell-wall is seen, and one of the 

 germs, covered with vibratile cilia, has 

 just effected its liberation, to be speed- 

 ily followed by the remainder. 



20. The higher forms of vegetable 

 life are only distinguishable from the 

 lower forms by the multiplication of 



voivoxgiobator, burst. similar cells, so that by the concur- 



rent labors of all, a more complete and lasting effect may be pro- 

 duced. 



21. The analysis of even the mighty monarch of the forest, shows 

 that all the soft and growing parts are composed of similar cells ; their 

 function is to absorb and prepare the nutriment, which is afterwards 



