CHAP. II. 
ROOT. 
8? 
tremity, when it is termed fusiform (or tap-rooted by the Eng- 
hsh, and pivotante by the French) ; or it dilates immediately 
below the surface of the earth into a globose form, when it is 
named turnip-shaped^ as in the common turnip ; if it is ter- 
minated by several distinct buds, as in some herbaceous plants, 
it is called many-headed (midticeps). 
The roots of many plants are often fleshy, and composed 
of lobes, which appear to serve as reservoirs of nutriment to 
the fibrils that accompany them; as in 
many terrestrial Orchideous plants, Dahlias, 
&c. These must not be confounded either 
with tubers or bulbs, as they have been by 
some writers, but are rather to be con- 
sidered a special form of the root, to which 
the name of Tubercules (fig, 43.) would not 
be inapplicable. In Orchis the tubercules 
are often palmated or lobed ; in the Dahlia, 
and many Asphodeleae, they hang in clusters, or are fasci- 
cidated. 
In internal structure the root differs little from the stem, 
except in being often extremely fleshy; its cellular system 
being subject to an unusually high degree of developement in 
a great many plants, as the Turnip, the Parsnep, and other 
edible roots. In Endogens, the mutual arrangement of the 
cellular and vascular systems of the root and stem is absolutely 
the same ; but in Exogens, there is never any trace of pith in 
the root. 
Sect. IV. Of the Appendages of the Axis, 
From the outside of the stem, but connected immediately 
with its vascular system, arises a variety of thin flat expan- 
sions, arranged with great symmetry, and usually falling off 
after having existed for a few months. These are called, col- 
lectively, appendages of the axis; and, individually, scales, 
leaves, bracts, flowers, sexes, and fruit. They must not be 
confounded with mere expansions of the cuticle, such as ra- 
menta, already described (p. 49.), from which they are known 
by having a connection with the vascular system of the axis. 
Till lately, botanists were accustomed to consider all these as 
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