HERBS (. BIENNIALS ) 15 1 
annuals are proletarians (p. 59). It is absolutely essential 
to the continuance of the race that plenty of seed should be 
set, and as a rule the flowers do not possess such mechanisms 
as risk in any degree the fulfilment of this end ; most are 
capable of self-fertilisation, and many are rarely if ever 
crossed. Vegetative reproduction is rare. 
In biennials, e.g. the carrot (Daucus), turnip, cabbage, 
kohl-rabi (Brassica), beetroot (Beta), parsnip (Peucedanum), 
&c., the case is different, and much storage of reserves takes 
place. During the first year the plant does not as a rule 
produce a tall stem or an inflorescence, but has usually a 
rosette of large radical leaves. The food-materials produced 
in these exceed the immediate requirements of the plant and 
the balance is stored up in the root, stem, or leaves which 
become thick and fleshy. The plant remains quiescent 
(> hibernates ) during the winter. Next spring a tall stem is 
produced, consisting chiefly of an inflorescence, and when 
the seeds are ripe the plant dies. Practically all the food 
required during the second year is derived from the reserve- 
stores, which become completely exhausted. An exaggera- 
tion of this feature of biennials — the storage of reserves to 
be used in a single flowering — leads to the peculiar cases 
of Agave and Furcraea, &c., which save up materials for 
many years and use them all in one great burst of flowers at 
the end. 
In perennial herbs, which live for several or many years, 
and usually flower each year, the vegetative period is gene- 
rally interrupted at regular intervals, either by winter, or by 
the dry season in hot countries ; the plant then as a rule 
dies down. Hence there must be a storage of reserves, to 
enable the plant to recommence its growth upon the return 
of spring (or the rainy season). This storage is usually 
made below ground, where it is well protected, and may be 
in the root, stem, or leaves. The part in which storage is 
made is more or less swollen, and if it include a bud is 
nearly always made to subserve the process of vegetative 
reproduction (p. 112). In many cases the original plant 
does not reappear in the second season, but a number of 
new plants formed from it by vegetative methods appear in 
its place. 
