_Vegetative reproduction._

Distribution by seed appears to satisfy so well the requirements of
Angiosperms that distribution by vegetative buds is only an occasional
process. At the same time every bud on a shoot has the capacity
to form a new plant if placed in suitable conditions, as the
horticultural practice of propagation by cuttings shows; in nature we
see plants spreading by the rooting of their shoots, and buds we know
may be freely formed not only on stems but on leaves and on roots.
Where detachable buds are produced, which can be transported through
the air to a distance, each of them is an incipient shoot which may
have a root, and there is always reserve-food stored in some part of
it. In essentials such a bud resembles a seed. A relation between
such vegetative distribution buds and production of flower is usually
marked. Where there is free formation of buds there is little flower
and commonly no seed, and the converse is also the case. Viviparous
plants are an illustration of substitution of vegetative buds for
flower.


_Phylogeny and taxonomy._

The position of Angiosperms as the highest plant-group is
unassailable, but of the point or points of their origin from the
general stem of the plant kingdom, and of the path or paths of their
evolution, we can as yet say little.

Until well on in the Mesozoic period geological history tells us
nothing about Angiosperms, and then only by their vegetative organs.
We readily recognize in them now-a-days the natural classes of