THE AWAKENING OF THE SEED 



65 



growth of the seed applies to the growth of all parts 

 of the plant at all stages of development. We may 

 cut off an inch from the tip of the root or stem and, 

 after measuring and weighing it, place it in water, 

 where it will continue to grow: we may then deter- 



53. Section of a bit of the seed-leaf of the Horse-bean, showing cells 

 filled with starch-grains {st), the protoplasm ipr) lying between 

 them, the nuclei (/i) and the cell- walls [cw). 



mine when the growth has "set" by the method which 

 we have just used for the seed. 



To get a better idea of the appearance of the cells, 

 we may proceed as follows : Holding a well - soaked 

 seed-leaf of the Horse-bean in the left hand, cut thin 

 sections with a sharp razor held in the right; cut 

 slowly with a drawing cut, place the sections in water 

 and select the thinnest ones, even though they be 

 very small pieces. Place them on a glass slide in a 

 drop of water, cover with a cover- glass and examine 

 under the microscrope. Fig. 53 shows the appear- 



