16 
MANUAL OF NATURE STUDY. 
leaves and notice the scaly covering in each case. 
Compare with naked buds in green house. Notice 
the sticky substance that holds these buds to¬ 
gether. Compare with naked buds. Bring up 
this question again in spring time when the buds 
begin to open. 
Compare the bark of plants that endure the 
winter, with that of green house plants. Why the 
difference ? Notice difference between bark of this 
year’s growth and that of last year’s growth. How 
does it differ at frosting time from the growing 
time? 
Notice that some plants, like the violet, spring 
beauty and potato, go into winter quarters under 
the ground just as some animals do. 
Observe that trees burst their bark when they 
get too large for it, thus making the outside very 
rough, as seen in the walnut or bur-oak. How 
about the locust or grasshopper, crayfish and cicada 
when they grow too large for their skins? The 
snake, frog, boy? 
6. Effects of Frost :—On leaves, buds, stems 
and flowers. The suggestions under (5) are ap¬ 
plicable here. 
Bring out the thought that some plants die 
down to the ground every year when frost comes, 
while others only drop their leaves. 
