26 OUR WOODLAND TREES. 
root, ig conical in shape. The opposite end, 
destined to grow upwards and develope into stem, 
branches, and leaves, is blunter; and this distinc- 
tion, in the incipient forms of the root end 
and the stem end of the avis—as this double germ 
of the plantlet is, from its central position, called 
—very nicely foreshadows the qualities of stability 
and penetration finally established in the future 
stem and in the future root. 
The surface of the integuments, or coverings of 
the vital parts of the plantlet, is pierced by a tiny 
aperture called the micropyle—a term derived from 
two Greek words, which mean a ‘ small mouth.’ 
This aperture is the opening through which 
the mysterious process of fertilization has been 
performed by the pollen of the fertilizing organ ; 
and it is to be especially noticed that the conical- 
haped radicle of the axis of the embryo is almost 
invariably found so placed as to point to the 
micropyle. 
But Nature is not content to make her enveloped 
seeds perfect in every part. She endows them 
with some quality which shall enable them, when 
freed from the parent plant, to find their proper 
