VEGETABLE STRUCTURE. 
141 
the conic clufters of VefTels in the head of the Root, and being formed 
within, as the Seed Leaves of the Radifh, ferves to keep up a return of 
Juices and to abforb moidure from the air ; and thus to aflilf in feeding 
the Plant. This fades as foon as the Bud is well formed ; and then begins 
a new growth, for the afiilfance of the Seeds : the great Placenta, the hrft 
rudiments of which appeared early in the Seedling Plant, now grows fa- 
llen ; and the Films in wliich the inner Rind of the Root terminated, begin 
to grow in length, and to loofen themfelves from the head. Thefe, b.ow- 
ever, make but flight advances during the appearance of the Flower, 
which dors not want their afilllancc; but w'hcn it has faded, they flioot 
filler ; and when the Seed-VdTel begins to fwell, they pierce the furface 
of the ground, and make fo many Leaves. This is the llate of the Plant 
reprelented at Fig. 7. 
The conflruction of Leaves has been Ihewn in the preceding Chapters, 
in the Seed-Leaves of the Radifli. All Leaves have the fame general for- 
mation, and the fame ufe. The difpofition of thofe Conic Clullers which 
make what we call the Ribs, conflitutes all the difference : They have 
Velfels which go and return, a^ thofe in the Flelh of the Plant from which 
they proceed, and with which they communicate ; and they are formed 
principally of a Blea with open cells, which difeharge and abforb, occaflon- 
ally, the moifture of the earth and air. Thefe Leaves are railed for the 
defence and nourifhment of the Seed-Veflel . they therefore do not appear 
till that rifes above the ground j and having ferved its purpofes, they fade. 
I'he Seeds are then ripened, and are fit for a new produce ; but as many 
of them mufl: fail in the uncertain way wherein Nature fows them, the 
Root remains to fupply the deficience. 
CHAP. XXXVi. 
The Course of the Juices in the Winter Aconite. 
T he Plant commonly known by this name. Winter Aconite, is 
properly of the Hellebore kind : Its Angular Nedlaria, its want of a 
Cup, and its Seed Veffels, fliew this evidently ; but while the diflindtive 
characters of Plants were lefs regarded, the fancy of Writers gave it this 
name; which cuftom flill preferves. It makes a natural advance from the 
Cholchicum, in the Vegetable Compofition ; being fomewhat more com- 
plex than that ; yet lefs fo, by many degrees, than the generality of Plants. 
Wfi 
