THE FORMATION OF FORESTS 103 
they fall to the ground, and even in a few cases 
while still attached to the parent tree, so that, in fact, 
the seedling and not the seed falls. 
The seeds of Castilloa elastica, the Centrait Amer- 
ican rubber tree, can be kept only a few days. Pack- 
ing seeds in charcoal, in air-tight boxes, may prolong 
their life, but in some instances, in spite of great 
care, the period of vitality is extremely short. Some 
seeds retain their vitality for several years. The 
statement that wheat seed, three thousand years old, 
from Egyptian mummy cases, germinates, is, how- 
ever, one of those lies which live on in spite of their 
preposterousness. 
When seeds are stored, they must be kept in a 
cool, airy place, which is neither too dry nor too 
damp. The outer encasements and hard shells of 
seeds perform the same functions that do the scales 
of buds. They protect the seed from the absorption 
and the evaporation of too much water. In fact, a 
seed is not unlike a bud. Both contain an embryonic 
individual which is capable of developing into a ma- 
ture organism, retaining throughout the characters 
of the parent which produced it. One, however, is 
sexually, and the other asexually produced. One is 
the result of the union of the male and female ele- 
ments of two individuals, while the bud is merely a 
vrowing point surrounded by nascent leaves and pro- 
