INTRODUCTION 
growth produce special thick leathery and often brown bud-scales which 
protect the buds — thence termed winter-buds — during the winter. These 
are thrown off when the bud begins to elongate in spring, leaving 
crowded scars, called ring-scars , round the base of the next season’s growth. 
In a variety of cases buds are capable of becoming detached and growing 
into new plants, a process termed vegetative reproduction , as distinguished 
from reproduction by seed. In Frog-bit and other water-plants, for 
instance, buds formed on lateral branches break off and sink into the mud 
as winter-buds or hibernacu/a , to form fresh plants in spring. Compact 
rudimentary buds, known as bulbils , are formed among the flowers of 
several species of Onion and become detached in a similar manner; 
and the short branches terminated in buds, known as off-sets , as in the 
House-leek, or the longer shoots which trail with several lateral buds 
from the Strawberry and are known as runners, by their decay detach 
young plants in much the same way. 
There are short shoots which remain for a time or permanently 
without elongation, so that the leaves they bear are crowded together; 
and long shoots which open out and so separate their leaves. Thus the 
leaves of the Larch are borne in clusters on shoots which elongate 
after the leaves have fallen, whilst the needles of the Scots Fir are in 
pairs on short shoots, which do not elongate. Flowers are, in fact, also 
short shoots. 
Many alpine and sub-alpine plants and some shore-plants, such 
as Primroses, Daisy, and Thrift are perennial herbaceous or slightly 
woody plants with a tufted mode of growth, the leaves often spreading 
out in a rosette. 
The stem , or ascending portion of the axis, differs from a root in 
its direction of growth, in growing at its apex, without any cap of dead 
tissue, in bearing buds and leaves, and in branching from 
its outer rather than from its inner layers of tissue. The 
main functions of the stem and its branches are, firstly, to convey the 
liquid food-material from the roots to the leaves, which have been aptly 
termed the laboratory of the plant, and to carry the sap elaborated in the 
The Stem 
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