Seeds and Seedlings. 7 



by separating the cotyledons, and draw to a scale suffi- 

 ciently large to bring out the details thus observed, say, 

 x 4. If any parts are folded together, make drawings to 

 show their relationship clearly. The student should not 

 be satisfied with his work until the drawings show the facts 

 as clearly as he can see them by a thoughtful examination 

 of the object. 



Germinating Lima Bean. 



5. Make drawings of a bean in the first stages of germi- 

 nation, and in various succeeding stages, identifying the 

 parts already studied in the ungerminated seeds. Note 

 any new structures. 



6. The following terms should now be applied in the 

 notes to the structures designated by them : 



The scar where the seed was attached to the pod is 

 called the hilum. 



The rudimentary plant formed in the seed is called the 

 embryo. 



The first leaves of the embryo are called the cotyle- 

 dons. 



The bud sometimes present between the cotyledons is 

 called the plumule. 



The small stem in the seed from which the cotyledons 

 grow is called the caulicle. 



The first root produced as a continuation of the caulicle 

 is called the radicle. 



All of the embryo below the insertion of the cotyledons 

 is called the hypocotyl (including caulicle and radicle). 

 All of the embryo above the insertion of the cotyledons is 

 called the epicotyl. 



The opening in the seed-coats near the tip of the caulicle 

 is called the micropyle. 



