SOIL FORMATION: ROCK DISINTEGRATION. 32$ 



empty cells absorb large quantities of water, and by capillarity 

 it is lifted on from one cell to another. These pendent branches, 

 then, which envelop the sphagnum stem, lift water up from the 



Where isoetes grows 



Fig. 268. 

 A small morainic basin near Ithaca. (Photograph by the author.) 



moist substratum to supply the leaves and growing parts of the 

 plant which are at the upper extremity. 



491, Increase each year. — Year by year the extension of the 

 sphagnum increases slowly upward by growth of the ends of the 



