64 SOILS AND PLANT LIFE 



and hypocotyl in each seed and where the food is stored 

 in each one. 



EXERCISE 19 



Object. — To study the parts of the seeds of the two 

 great classes of plants. 



Procedure. — Soak a few beans and grains of corn for 

 an hour or more. Shave away the entire face of one of 

 the grains of corn on the germ side with a sharp knife. 

 When the plumule and hypocotyl are plainly visible, set 

 the kernel up where you can see it easily and make a careful 

 drawing. 



Open the halves of a bean, being careful not to break the 

 plumule and hypocotyl, which lie near the spot where the 

 bean was attached to the pod. Make a drawing of one 

 half of the bean, showing the parts in place. 



Label all parts in both drawings. 



Conclusions. — State fully in what respects the two 

 embryos are alike and in what respects they differ. Do 

 not fail to explain clearly where the food that is provided 

 for the Uttle plant after germination is stored in each seed. 



46. The Conditions required for Seed Germination. — 

 When the right conditions surround a living, mature seed, 

 the embryo awakens, sprouts or, as we say, it germinates. 

 We are at once interested to know what these right condi- 

 tions are and how far it is within the power of the farmer 

 to provide them. Let us state and then prove that before 

 a living seed will germinate, it must have (1) oxygen, 

 (2) a proper amount of moisture, and (3) a proper tempera- 

 ture. 



EXERCISE 20 



Object. — To prove that a seed must have oxygen in 

 order to germinate. 



Procedure. — Fill a jelly glass or a pint fruit jar half 



