BIOLOGY OF HIGHER SEED PLANTS 63 



given in the text. Would the eosin rise in the 

 stem as rapidly as pure water ? Kecord results. 

 b. Path of water ascent in the stem and leaves. 



(1) Cut the stem lengthwise through a node and trace 



the path of the eosin from the main stem into 

 the leaves and branches. 



(2) Draw a transverse section and a long section of the 



stein, indicating the tissue in which the eosin solu- 

 tion moved. Did it pass up the ducts or in other 

 tissues of the xylem and phloem ? 



(3) Plot the path in the leaf veins and veinlets. 



ECOLOGICAL RKLATIOX OF PLANTS TO WATER 



1. Make a list of 10 mesophytes, 10 hydrophytes, 5 xero- 



phytes, and 10 tropophytes from the wild and culti- 

 vated plants of your own region. Be able to explain the 

 gross structural adaptations of these plants to their 

 habitat. 



2. Are some of the above plants apparently not adapted to 



their present habitat ? If so, how do you explain this ? 

 Be able to give the essential characteristics of the 

 mesophytes, hydrophytes, xerophytes, and tropophytes 

 of your region. 



