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FRANK C. GATES 
demands upon the main root. Usually the old stem does not die off, 
although it may shrivel somewhat. If however, the old stem is cut 
off, the plant continues to develop, obtaining its water supply entirely 
from side roots. 
The youngest part of the stem is the most fleshy. As it becomes 
older it becomes less fleshy, but retains approximately its maximum 
Fig. I. Vines of Raphidophora merrillii Engl, growing on a leaning mango 
tree, illustrating the fact that the stem is progressively thicker in its younger portions. 
Los Banos, P. I., Nov. 3, 1913. 
diameter. As the whole plant becomes larger the increasing in 
thickness of the newly forming stem continues, but at a much slower 
rate, so that a stem of Raphidophora 4 cm. in thickness is very unusual. 
Douglas Lake, Michigan 
