WALDRON— THE PEANUT 327 



two weeks, followed by a period of very moderate development. 

 Audouard"^ states that the plant grows slowly during the first half 

 of its existence, and that the most rapid growth takes place after 

 about ten weeks. This indicates a relation to the formation of the 

 gynophore and root tubercles again, both of which appear later. 

 This makes possible a greater activity in growth of the plant. One 

 feature somewhat difficult to understand is the presence of the num- 

 erous stomata on both epidermal layers. How is the water balance 

 kept with such a reduced hair surface, especially on the roots of 

 plants not yet producing fruit? 



If the seed is deep, the hypocotyl elongates accordingly. If the 

 seed is planted in the shell, it will push up through three or four 

 inches of soil. It is often much curved and twisted in its efforts 

 to extricate the cotyledons from the shell. These remain green for 

 two or three weeks, when they wither and drop. Concerning the 

 presence of food materials during growth Audouard states (i) that 

 there is sugar in all parts of the plant, which decreases in amount 

 during fruit maturation; (2) That starch in the root and stem in- 

 creases from the beginning to the end of vegetation; (3) that fats 

 increase for six to nine weeks, that is, until the fruiting period, when 

 they suddenly decrease in the vegetative organs; (4) that proteins 

 decrease in roots and stems at flowering time and increase in the 

 fruit. The writer has observed that the gynophore is well stored 

 with starch until the ovary begins to grow, when apparently much of 

 it is carried as sugar to the inner fruit tissue, forming there the 

 broad, delicate-walled sugary endocarp (see page 319), — thus the 

 reason why immature fruits are sweeter. Some of this sugar at 

 least is apparently gradually transferred to the testa and there 

 stored temporarily as starch. Later, both this and that from other 

 sources (gynophore and stem) are transferred to the cotyledons and 

 largely stored as oil. Since the carbohydrates are early furnished 

 and carried to the gynophore and stem, the thought arises as to the 

 possibility of the fruit maturation being largely independent of the 

 roots of the plant. The other food materials can be obtained from 

 the soil by the fruit, and proteins can be formed in darkness, so there 

 is no known reason why this should not occur. 



Biological Considerations Concerning the Fruit and Gynophore. 



Observations on the Gynophore. In his work on "The Movements 

 of Plants,'" Darwin"^ says that while apheliotropism may act in 



