V. FRUITS AND THEIR USES 



Problem VIII. A. study of fruits to discover 



(a) Their uses to a plant. 



(&) The means of scattering. 



(c) Their protection from animals and other enemies. 

 (.Laboratory Manual, Prob. VIII.} 



A Typical Fruit, the Pea or Bean Pod. If a withered flower 

 of any one of the pea or bean family is examined carefully, it will 

 be found that the pistil of the flower continues to grow after the 

 rest of the flower withers. If we remove the pistil from such a 

 flower and examine it carefully, we find that it is the ovary that 

 has enlarged. The space within the ovary has become almost filled 



with a number of al- , 



most ovoid bodies, at- 

 tached along one edge 

 of the inner wall. 

 These we recognize as 

 the young seeds. 



Fruit of the black locust ; a legume, showing the 

 attachment of the seeds. 



The pod of a bean, 

 pea, or locust illustrates 

 well the growth from the flower. The flower stalk, the ovary, and 

 the remains of the style, the stigma, and the calyx, can be found 

 on most unopened pods. If the pod is opened, the seeds will be 

 found fastened to the ovary wall each by a little stalk. That 

 part of the ovary wall which bears the seeds is the placenta. 

 The walls of the pod are called valves. 



The pod, which is in reality a ripened ovary with other parts of 

 the pistil attached to it, is considered as a fruit. By definition, 

 a fruit is a ripened ovary together with any parts of the flower that may 

 be attached to it. The chief use of the fruit to the flower is to hold 

 and to protect the seeds ; it may ultimately distribute them where 

 they can reproduce young plants. 



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