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ers of the periblem tissue taking the place of an epidermis. As 
growth continues it appears that the outer layers do not keep pace 
with the inner, and cells of the surface are continually peeling off 
in rows or single layers many cells in length. 
À cross section of a young root shows the outer layers of cells 
separating from the inner tissue and from each other by large in- 
tercellular spaces, and individual cells may be seen entirely isolated. 
In this view the peripheral three or four layers of the tissue of the 
Cortex appear as an irregular zone, several cells deep, composed 
of cells which resemble the rest of the rind cells in shape, but 
which are much smaller. e 
These cells are thin walled like the remaining rind parenchyma, 
and are distinctly cutinized around their whole circumference. 
Thin sections as well as masses were placed in concentrated sul- 
phuric acid. It was found that the walls of an outer portion, 
composed of these cells described, turned brownish yellow and 
remained intact, while the rest of the tissues of the parenchyma 
disappeared in a few hours. This cutinized portion was from two 
to three cells deep. The walls of the outer cells were entirely 
cutinized, while those of the cells next below these were cutinized 
on the side toward the circumference only. 
The lateral roots show the same peculiar lack of epidermal tissue 
and, of course, no hairs appear. In other respects their anatomy 
resembles that of the ordinary dicotyledonous root. As they in- 
crease in age their outer surface is supplied with a regular peri- 
derm, and it is only in the early stages of growth that this peculiar 
habit may be observed. 
Biological Considerations, 
As the plant is only found under cultivation, at the present 
day, it is impossible to estimate in what degree its habits may 
have been influenced by its artificial surroundings. If, however, 
the changes induced by cultivation are generally in the direction 
of the inherent tendencies of the plant, emphasizing rather than 
changing such tendencies, the fact of cultivation would not enter 
largely into the question of the biology of Arachis. 
The question of the course of the downward direction of 
Srowth of the gynophore has been answered by Charles Darwin, 
