22 THE NATURAL HISTORY OF BRITISH GRASSES. 
form in individuals of each species, yet in their variations 
in species make up the sum of those distinctive characters 
which enable the botanist to separate one species from 
another. Such are— 
The Root, or descending axis, consisting of root-fibres 
and rhizome. 
Culn, or ascending axis, consisting of stem, with its nodes 
and joints. 
Leaves, the appendages of the axis, consisting of sheath, 
ligule, lamina. 
Flowers, or reproductive organs, consisting of floral enve- 
lopes, stamens, and pistils. 
Seeds, or Fruit, consisting of grains of various forms and 
sizes. 
The roots of grasses usually consist of small fibres, which, 
in starting from the seed, burst through the radicle, or seed- 
root, like the inner valve of a telescope from the outer; 
this, which is called by botanists Endorhizal, from two 
Greek words signifying within a sheath, may be well ob- 
served in the germination of such large grasses as are 
presented in the cereals, as wheat, barley, &c. Roots are 
sometimes hard and wiry, especially in such species as grow 
in damp and boggy places; whilst in others they are exceed- 
ingly flexile, the main roots often creeping great distances 
in search of food, and then branching off into innumerable 
fibrils, or rootlets, the ends of which, consisting of the 
newest cells or growth, form the spongioles, or suckers, by 
which nutriment is taken from the soil into the plant sys- 
tem. Itis hence necessary, in the cultivation of grasses, 
that the soil for the reception of the seed should be of good 
tilth, and especially that its mechanical consistency should 
be such as that it will not greatly expand in moisture, and 
so push the plants out of place—or crack in drought, in 
which case the rootlets, or active parts in life and increase, 
are broken away just at the period when they are most 
required. Roots are without buds, from which it will be 
seen that all the parts of a grass which grow beneath the 
