VEGETABLE STRUCTURE. 
171 
made up of the abfolute Pith, and covered with Membranes formed only 
by its hardening Juices, Fig. 2, k. 
If we begin at the infertion of the Leaf, cutting the Flowerftalk half 
thro’, and gently fcparating its feveral fubftances, we fliall firft take up a 
tough and firm Skin : tliis is the outer part of the prefent Stalk, and it was 
the fecond or inner Rind in that below. It was there purple ; it is lure 
greeriifii : but it has fiill fomeihing of the original hue. Jf we draw a 
part of this off carefully to the head, we lhall take off with it one of the 
three outer Petals. This Petal is a plain and evident continuation of its 
fubflance : as plain as the continuation of the outer Rind into the Leaf 
upon the Stalk. The formation of the Petal from the Rind, is this at the 
point of the Flowerftalk which makes its fummit, and where the Conic 
Clufters form that fmall head, the Receptacle of the Flower, this Rind 
of the Stalk fwells into a kind of knot : juft as the outer Bark did at the 
origination of the Leaf; and in this Knot or Gland, for fuch it truly is, 
the VelTels of the Rind which form it have many interweavings one with 
another, and fwell out into little lumps. From thefe rife the VefiTcls of the 
Petal. But to underhand this we muh trace the matter yet deeper. 
This fecond Rind of the Stalk, which appears outermoft in the part 
now under examination, is not a fimple Film, but has, as that of the 
Hellebore, and other Plants, a regular and large arrangement of Vefiels. 
Thefe are connected by two Films, which are mere fimple Meiribranes. 
In this form the Rind runs up to the head of the Stalk, where it makes a 
peculiar Gland, and is thence continued into a Petal. The Vefids inter- 
weave with one another, without inofculation, and make the body of the 
Gland : this feparates the two Films, which contained them in the com- 
mon courfe of the Rind, to fuch a di lance that the three par's can be 
feen diflindtly. The Films ftill cover the Gland, as they did the Vefiels 
in the Rind, and they are continued upward into the two fides of the 
Petal, Fig. 2, /, g. Thus one part of the Vegetable Syflem ferves to 
explain another; and the courfe of Nature being underfiood, is followed 
eafily. 
The body of the Petal is compofed of three fubfiances, a vafcular part 
in the center forming a kind of Flefli, and two Membranes, oiie on each 
fide. The Rind itfelf is formed of the fame parts, only they are more 
diftindt in the Petal : and the ufe of the Gland is to give the fubfiance of 
the Rind a kind of Root, full of nourifliment, by means of which it may 
expand and form thefe Petals. 
Z 2. 
In 
