INTRODUCTION 
The chief functions of the root are to anchor the plant in the soil, or 
in whatever substratum it may grow ; and to take in liquid food- material. 
This latter function is generally performed by minute delicate root-hairs, 
which are produced on the younger part of the roots just behind their 
growing region. In some cases, however, these root-hairs are absent and 
absorption takes place through the surface of the young root, or by means 
of a mass of filaments formed by a fungus which lives in a condition of 
partnership or symbiosis (Greek vvv, sun , together; /SiWis, biosis , life) with 
the root. Such fungi are termed mycorhizce (Greek ixvKrys, makes , fungus ; 
pi£a, rhiza, a root). In the Pea and Bean Family and some other plants 
tubercles are formed on the roots by bacteria, which are of service to the 
plant, since they are capable of absorbing the free nitrogen of the air. 
In many plants, mostly biennials or perennials, i.e. plants taking more 
than a year to complete their life-cycle, the roots are enlarged so as to 
serve as reservoirs of nutriment for growth at a later stage. This is the 
case with the tap-roots of Carrot, Turnip, and Radish already mentioned, 
with the tubercular roots of the Lesser Celandine and many Orchids, the 
fasciculate or clustered roots of the Water Dropwort ( CEnanthe ), and the 
nodulose adventitious roots of Dropwort ( Spircea Filipendula). 
Very few Flowering Plants, such as the Bladderwort, are without 
roots ; but these and other submerged aquatic plants are capable of 
absorbing water from their general surfaces. 
The plumule, or primary shoot in the seed, rises above ground in 
sprouting as a stem bearing leaves, growing generally upwards, away, that 
is, from the centre of gravity. It originates as a bud, or 
The Shoot . . . « . «. 
growing-point, protected by over-arching rudimentary 
leaves ; and as long as the stem or its branches are in an actively growing 
condition they are terminated by similar buds. The terminal bud of 
the main stem is often called apical ; and the branching of the stems of 
Flowering Plants originates in the development of buds, which are 
generally formed in the axil of a leaf (Latin axilla, the arm-pit), i.e. the 
angle between the base of a leaf and the stem, and are, therefore, termed 
axillary. Trees and shrubs generally at the close of the season of active 
XVI 
