12 



TRADESCANTIA. 



[CH. I 



In the same way the plant may cease to bubble for want 

 of raw material (CO 2 ) or for want of driving power (sun- 

 shine) or because the machinery is broken, i.e. the 

 chlorophyll-bodies killed. 



Tradescantia, Elodea, Elder. 



The present chapter is intended to give a somewhat 

 wider introduction to anatomy and physiology of the 

 plant-cell than can be obtained from a study of yeast 

 and Spirogyra. Parts of certain higher plants have there- 

 fore been included in the Practical Work. 



! 



c 



D 



FIG. 3. 



CELLS UNDER HIGH POWER. 

 A, B, young cells, C an older cell from the developing maize-root. 



D, cell from the hair of Tradescantia. 



E, parenchymatous cell from the cortex of Kanunculus. 



A hair from the stamens of the Spider- Wort (Trades- 

 cantia virginica) consists of a row of rounded cells united 

 end to end. Under the microscope can be seen the 

 purple cell-sap which occupies the greater part of the 

 cavity of the cell The protoplasm is more easily visible 



