GERMINATION OF THE SEED 177 



(a) The position of the seed as 



planted ? 



($) Any feature of the environment ? 

 (8) What are the relative positions of main 



and side roots ? 



Answer by a fully labelled sketch of a typical 

 specimen, and, where necessary, concisely in 

 words. 



11. Study in the same manner the germinating Horse 



Bean. 



12. Study in the same manner the germinating Morn- 



ing-glory. 

 1-3. Study in the same manner the germinating Corn. 



14. Select any one of the above kinds of seeds, and 



make a series of outline drawings to illustrate 

 Exercise 10 (7). 



15. Your studies (Exercises 10 (7) and 14) have shown 



you that the positions taken by hypocotyl and 

 plumule in growth are entirely independent of 

 the position of the seed from which they came. 

 Their up-and-down position suggests that gravi- 

 tation may have something to do with it. To 

 test this, the logical plan is to place two sets 

 of seeds under conditions precisely alike, except 

 that gravitation is allowed to act upon one set 

 and not upon the other. Since, however, nothing 

 upon the earth can be removed from the influ- 

 ence of gravitation, it is necessary so to arrange 



N 



