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PORJLAR SCIENCE REVIEW. 
for that purpose. They are devoid of chlorophyll or leaf-green, 
and without pores. In some instances their surface is clothed 
more or less densely with hairs, or it is covered with glands 
which exude a copious resinous or glutinous secretion, with 
which the surface of the hud is overspread. These leaves are 
thus organized in order that they may protect the next year’s 
foliage, blossom, and fruits. All the beauty and glory of the 
vegetation of the coming year is left in the charge of these 
inconspicuous bud-scales or winter’s leaves ; for every leaf 
and blossom is already formed and securely packed away into 
the smallest possible space in these buds, under the air and 
water-tight roofs formed by them. In order to verify these 
facts, it is only necessary to dissect one of these buds, by 
removing its scales, and examining the embryo leaves in its 
interior with a microscope. The bud of the horse-chestnut is 
one of the best that can be selected for this purpose. The 
embryo leaves will be found in the interior of this bud, in a 
warm bed of tomentum or down, packed away securely for the 
winter. 
The winter leaves or bud-scales continue attached to the 
trees throughout the winter months; but when spring comes, 
and the summer leaves which they have protected are pushed 
out into the air, the tree shakes off its winter leaves on the 
green grass carpet, exactly in the same way as it does, later in 
autumn, its summer leaves. So from all the trees of the forest 
there is every year a double leaf-fall. The fall of these winter 
leaves is beautifully seen in the beech, maple, and horse- 
chestnut ; and, as we have already remarked, an observer of 
nature will experience no little gratification in studying these 
little obscure though important folioles. The bud was called 
by Li imams the liybernaculum or winter-quarters of the shoot; 
and buds with the winter leaves on their exterior may also 
be regarded as them winter defences. The winter leaves are 
organized to protect the life slumbering in the buds against 
the cold of this season of the year. A low temperature appears 
to be necessary to their life, for as soon as the warm days of 
spring commence and the summer leaves come out, they fall 
from the tree. These winter leaves cannot, therefore, live 
under the same circumstances as the summer leaves ; and the 
winter atmosphere in which they live and discharge so faith- 
fully their protective duties to the summer leaves would destroy 
the life of the latter. 
As the summer leaves make on the stem a cicatrix or scar 
which shows their former point of union, so with the winter 
leaves ; these also leave their mark or scar ; only in this instance, 
the internodes or naked intervals of stem between the leaves 
are suppressed, the scars are necessarily close together, and 
