202 PRINCIPLES OF BOTANY, ETC. 
i some of the creeping roots. A strawberry plant, 
in a garden of excellent soil, was planted in a par- 
ticular spot filled with sterile sand. Stalks and roots 
all orew out towards the sides where the good soil 
vas, but the main plant decayed. Several other re- 
drs instances are, at present, inexplicable, as 
we know so little of the physiology of plants. 
§ 256. 
This part of the plant, then, which we know un: 
der the name root, however various ‘its shape may 
be, has always fibres or radicles, to which’ alone 
physiologists choose to give the appellation of root. 
These radicles, like the leaves, are annually renewed. 
During spring and autumn, in cold and temperate 
climates, even in winter, when the whole ground is: 
covered with snow, new ones spring in place of the 
old-dry ones. In warm and hot climates this hap- 
pens during the rainy season, therefore always at a 
period when the vegetable world appears to be, as 
it were, in a slumber. ‘The radicles grow in the 
following manner: a small bundle of air vessels 
erows larger, pierces the cutis, and runs into the 
yround. It is inclosed in a delicate cellular texture, 
covered by a membrane and other more delicate — 
vessels, ‘Thus the extreme point of such a radicle 
is merely the end of the spiral vessels, which ab- 
sorbs the necessary food from the soil, (§ 274). 
These fibres, which are never wanting in plants, can- 
not perform this function of taking up food longer 
than one summer, after which they must be suc- 
ceeded by new ones. 
