178 THM NATURE AND WORK OF PLANTS 



anotlier, special varieties are propagated without 

 the use of seed. The forms developed in this 

 method are very widely different from the type of 

 the species, and when a seed of a fruit borne on 

 one of these grafted branches is planted, it produces 

 a tree which is unlike the characteristic branch from 

 which it sprung, and it is said not to " come true." 

 As a matter of fact the seedling does come true to 

 the species, but not to the cutting or grafted branch 

 from which it sprung. 



217. TJie bean and pea. — Examine a flower of 

 the bean and pea. Note the characters of the dif- 

 ferent parts of the flower. Describe the number and 

 arrangement of the stamens and pistils. Is pollina- 

 tion aided by the wind or animals ? Follow the 

 development of the pistil. From what is the pod 

 derived ? Note the manner in which the pods open, 

 and the position of the seeds which fall upon the 

 ground. How far are they thrown from the parent 

 plant ? Do the pods open forcibly ? 



Describe and draw the outward appearance and 

 form of the seeds. Note the number and character 

 of the coats. 



A number of peas and beans should be placed in 



