VEGETABLE STRUCTURE. 
118 
the fmaller number below, but are produced anew in the parts where 
they are found. The courfe of thefe tubes of Flefh is eafily traced up- 
wards, in the Footdalk, to the place where it expands into a Leaf. 
As the Seed-Leaf is an abfulute expanfion of the Footftalk, and nothing 
more; there can be no fixed point aligned, where the Stalk ends, and 
where the Leaf begins: but if we obferve the pare a, in Fig. 52, as the 
beginning of the Leaf, we flaall Le readily what courfe the three tubes of 
Flefli, with their clufiers of Vtfiels, take. The Fig. 52, reprefents a 
perfect Seed-Leaf, with its Footfialk a little enlarged. In this we fee, 
even in the Footlfalk, the three flefliy bodies : the largeft, b, runs up the 
middle, and the two others, c c, uniting again toward the bafe of the 
Leaf, as they did at their rife, run up the two edges. When tlie Stalk 
fpreads into a Leaf, their courfe is not altered, the flefiiy body, keeps its 
rout uninterrupted up the middle of the Leaf, and becomes what we call 
the Middle Rib; and the two others keep alfo their coun'e along the two 
fides of the Leaf Titere are two or three fubordinate Ribs alfo, which 
rife from the principal or middle Rib in the body of the Leaf; but thefe 
are altogether dilbindt : they are fent cfF from the princip.'il flcQiy Tubes; 
whereas the two dillindt fide Ribs have fliared its origination, and rofe 
with it. 
If we trace fiifl the two fide Fibres of the Leaf, we find them in their 
paflage divefed wholly of the coat of Flelh which covered tliem in the 
Fcotftalk : this grows thinner as it approaches the part a, Fig. 9 1 ; and 
at a little fpace higher in the Leaf ceafes entirely. We have fecn tliat the 
whole of th's body was a Tube of Flefli with two of the Conic Cliiflers 
ofVefiels; as the tube of FIclli dimiiiKhes to nothiing on enttrin:; the Leaf, 
we fee in the upper part of the Leaf the Conic Cluflirs treed from any 
covering. Thefe Clufiers are formed partly of green Vefiels, and partly 
of a white fpungy matter ; even thefe confiituent paits of tlie Conic Cluf- 
ters feparate in the body of the Leaf; the two Clufiers of reen \TfiMsrLm 
updifiindfat a fmall dillance from one another, and the white fpungy mat- 
ter is placed in a large body between them, and in feme degree alfo fur- 
rounds them. 'I'he middle Rib being more co.mpadt, does not feparate 
fo much ; but ufitally its two Clufiers may be fetn very difiindtiy, and the 
better as their Juice is red. Th.e courfe of thefe Vefiels is reprefented at 
Fig 52. 
The Seed-Leaf is compofed of all the fubfiances we h.ave fecn in its 
Footfialk, except the Fiefli : and they are thus difpofed. 'I’h.e outer Bark 
of the Footfialk, which is a continuation of that of the Root, forms what 
we 
