58 
Peirce. — A Contribution to the 
the seedling be greatly increased, and the neither thick-walled 
nor strongly-cutinized epidermal cells of the stem be unable 
to counterbalance the loss by their own absorption, the 
growth of the seedling will be greatly lessened in speed and 
amount, and thereby its chances of finding a suitable support 
will be diminished. Any dry object with which it comes into 
contact also draws water from it. Hence it is evident that, in 
this respect at least, it is disadvantageous to the plant to wind 
about dry and innutritious supports. The length to which 
the seedling can grow is proportional to the amount of water 
which it can absorb and retain, that is, to its turgescence. 
Seeds sown on sunny dry beds in the garden germinate 
slowly, the roots of the seedlings die soon, the stems attain 
a length of only a few centimetres, usually not more than five, 
unless a host be quickly found. If, on the contrary, the bed 
be a moist and shady one, or still better, if the seeds be sown 
on damp earth in a pot covered by a bell-glass, the seedlings 
can attain surprising lengths. Not only is the total amount 
of growth greater, but the length of the living part of the 
seedling is also greater. From the dying root most of the 
nutritive materials are removed to younger parts. Thus fed, 
the tip of the stem can continue to grow, and thus the area 
explored by it in its circumnutation is increased. Not only 
does the dying root yield its substance for the nutrition of the 
tip of the stem, but the stem dies also from below upwards, 
and from it too the nutritive substances are transferred to the 
youngest parts. Owing to the ability of the growing part to 
extract food from the oldest and least useful parts, the seed- 
ling is capable of a slow locomotion. The advantage of this 
is quite obvious, for in this way the seedling can approach 
a suitable plant which was at first beyond reach, and finally 
can lay hold on it. 
If the root be not already dead before the seedling has 
found a host about which it can twine, it quickly dies when 
the youngest part of the stem begins to wind. The direction 
of winding in every case which has come under my observa- 
tion was in the direction of circumnutation, namely the reverse 
