THE PLANT GROUPS 115 



5. Distinctive characteristics. Summarize in your notes 

 under the above headings (namely, body plan, leaves, 

 roots, and the tropisms of the central axis and lateral 

 organs) the distinctive characteristics of ferns as com- 

 pared with higher plants. 

 0. Drawings. 



a. Make an. accurate drawing of the fern examined. 

 I. Bring out as largely as possible, in the main drawing 

 and, where necessary, by detailed drawings of certain 

 organs (for example, leaves), the distinctive charac- 

 teristics of ferns named above under 5. 

 c. Draw an outline figure, indicating the positions assumed 

 by_the organs in a cultivated or wild fern. Indicate 

 stimuli and the nature of the response of the plant 

 organs by use of the proper terms, as in the earlier 

 studies of seed plants in Part I. 

 7. Habitat, habit, and environment. 



a. Habitat. What is the common habitat of ferns in your 



region ? Are they typically mesophytic, xerophytic, 

 or liydrophytic ? Do you know of exceptions to the 

 general rule ? 



b. Environment. Compare the environment of common 



wild ferns growing on the forest floor with ferns 

 growing in homes, and with common seed plants 

 growing in the open. How would these three habi- 

 tats compare as regards heat, light, soil water, food 

 elements in the soil, and the relative humidity of 

 the air ? Answer these questions in a paragraph 

 in your notes. 



c. Habit. How is the habit of wild ferns especially adapted 



to the above environment as regards the form, size, 

 and texture of the leaves ? Do cultivated ferns mani- 

 fest a different structure ? 



