CHAP, xxxn SEED DISPERSAL BY WATER 125 



CHAPTER XXXII 



SEED DISPERSAL BY WATER 



MANY marsh plants growing near running or even quiet 

 waters, upon the margins of the ocean, or in the water itself, 

 depend in most cases upon the currents of water or upon the 

 breezes at the surface of the water for their dispersal. They 

 are usually, therefore, rendered buoyant in some way or 

 other. 



I. Examine a Cocoanut, still retaining its husk, and 

 notice : 



1. The general shape, size, color, etc. 



2. The attached end. 



3. The opposite pointed end. 



4. The three blunt angles (longitudinal). 



5. Make a sketch to show these points. 



II. In a Cocoanut which has been cut into two longitu- 

 dinal halves, examine one of the cut surfaces and notice : 



1. The outer thin, firm, smooth skin. 



2. The fibrous portion of the husk. 



3. The shell (seed-coats) of the nut. 



4. The " meat " (endosperm) of the seed. 



5. The small embryo under the " soft eye " at one end. 



6. Make a sketch of one of the cut surfaces. 



III. Examine the bladdery fruits of some Sedge or the 

 seeds of the Water-Lily, if obtainable and notice their buoy- 

 ancy in water. 



