276 Field, Forest, and Wayside Flowers 
the needles issuing from the bud we have observed 
one of the characteristics by which we may deter- 
mine its species. 
After the leaf-cluster is mature the little brown 
bud-scales which sheltered its youth drop away and 
fall. A slow, gentle shower of them drips earth- 
ward in the pine-woods all through the latter year, 
and adds largely to that soft, mouldering carpet 
which covers the ground beneath the trees. 
In the balsam-fir and in the yew-tree each needle 
has its own guardian scale-leaf, and the foliage is 
distributed evenly over the surface of the bough 
(Fig. 77). 
Within the needle-like leaves of the pines and 
their cousins there is no delicate network of 
branching-veins such as we see in the foliage of 
oaks and maples. Instead, there is one compact 
bundle of vessels and tubes, through which plant- 
fluids creep out toward the sunlight to be 
digested, and then back again to growing roots and 
shoots. This bundle lies at the very centre of the 
leaf, and is sheathed, and in a measure protected 
from cold by an enclosing tube of thick cells with 
corky walls. Outside this corky tube lies the 
green substance of the leaf, composed of delicate 
cells containing chlorophyll. 
