MANUAL OF NATURE STUDY. 
127 
are usually left alone by nature, covered with 
leaves. Ask the children their experience in win¬ 
ter, if they have traveled through the woods. If 
they have no experience to relate, it will be well to 
send them through the woods in dead of winter, or 
better towards spring to find beech nuts, acorns, 
hickory nuts, walnuts, hazel nuts, crabapples, wild 
plums, wild grapes, etc. It is more than likely that 
fully half of the number gathered in this way will 
have already lost their vitality for germinating, but 
of those which are alive, nearly all have been nicely 
covered with leaves as a protection from frost and 
water. Then, again, the seeds are more or less 
oily and thus offer resistence to cold and wet. In 
the majority of cases the outside hull or shuck 
keeps off the water and sudden frost. 
But there is another kind of fruit that does not fall 
with the coming of frost. See (2) of this report. 
Many of this kind of fruit open by means of 
valves, teeth or pores, and frequently the seeds are 
persistent long after the splitting of the pods. And 
as these pods generally open at the apex, provision 
must be made to protect the seeds against rain or 
snow. 
This is done by a peculiar quality of the pod, 
which attracts the water in such a way as to form a 
film of oily moisture over the seeds, and this film, if 
left undisturbed, will prevent the water from 
