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and it was never found in the part above, except as it may be 
considered represented by the lenticels. 
As the walls of the new cells are never suberized it may be 
suggested that one possible reason for their formation is to increase 
the number of cells near the surface, where the water from the soil 
comes in through the hairs. Their small size, however, seems to 
refute this idea, and even were it admitted as a reason it would not 
account for the increase of cells occurring only below ground. 
Why do they not increase during the entire length of the 
organ, and thus present a normal condition agreeing with the typ- 
ical stem? Whatever may be the answer to this question, the in- 
crease in the number of cells does furnish an additional reservoir 
of some considerable size for the water flowing in from the hairs. 
In regard to the roots it is a well-known fact that the few 
Angiosperms that are known to be without root hairs are either 
plants which grow from bulbs and, therefore, do not require much 
nourishment from the soil, or water plants whose epidermis takes 
the place of root hairs, or epiphytes which also have no use 
for these organs. Arachis differs from all of these, not only in 
its need of food from the soil, but in the fact that it lacks both 
root hairs and a normal epidermal covering on those portions of 
the root where the hairs should develop. This latter fact points 
to the possibility that through this it has lost the power to pro- 
duce hairs, which at one time belonged to its ancestors. 
If this be true, the purpose of the gynophore cannot be simply 
to secure more nourishment than can be supplied by the roots, for 
they have los? the habit of forming hairs, showing that no great 
demand for food supply has been made upon them. If the plant 
does not require more nourishment from the soil than might be 
supplied by root hairs and yet forms such hairs on the gynophore 
instead of the root, we are forced to the conviction that for some 
reason it is advantageous to it to take its supply of food from the 
gynophore rather than the root. What reason can there be but 
one which has for a motive the welfare of the seed ? 
It has already been suggested that the plant needs to secure 
its seeds against the danger of being eaten by grazing animals. 
If this were in fact the purpose it may be seen how the conditions. 
discovered facilitate its accomplishment. The fruit is not developed 
