LEA 
be laid according to either of the four firft ways of 
laying, but too much head muft not be left on, left 
that be injured by the wind, or by its own motion 
rub off the tender root and the fmaller the boughs 
are, the lefs way they fhould be left out of the 
ground, and care muft be taken to keep them clear 
from weeds. 
The harder the wood of the tree is, the young fhoots 
will take root beft ; but if the wood be foft, the older 
boughs will take root the beft. 
There are many kinds of trees and plants which will 
not put out roots from their woody branches, though 
laid' down with thd utmoft care ; yet if the young 
fhoots of. the fame year are laid in July, they will often 
put out roots very freely, fo that when any plants are 
found difficult to propagate by Layers in the common 
way, they ftioulcl be tried at this feafon but as thefe 
fhoots will be foft and herbaceous, they muft not 
have too much wet, for that will caufe them to rot; 
therefore it will be a better method to cover the fur- 
face of the ground over the Layers with Mofs, which 
will prevent the ground from drying too haft, fo that 
a little water now and then will be fufficient. 
LEAVES. A Leaf is defined to be a part of a plant 
extended into length and breadth, in fuch a manner 
as to have one fide diftinguiffiable from the other •, 
they are properly the moft extreme part of a branch, 
and the ornament of the twigs, and confift of a very 
glutinous matter, being furnifhed every where with 
veins and nerves •, one of their offices is, to fubtilize 
and give more fpirit to the abundance of nouriffiing 
fap, and to convey it to the little buds. 
We fhall firft confider the diftinffions which are made 
by botanifts in their definitions of the fhape and form 
of Leaves in their titles and defcriptions of plants, and 
afterward confider their ules in vegetation. 
The Leaf of a plant or tree is diftinguiffied from that 
of flowers, the firft is called Folium in Latin, and the 
other Petalum ; therefore what is to be underftood 
here of Leaves, are thole which are ranged on the 
branches and ftalks of plants, and have no connexion 
with the flower. 
Thefe Leaves are either Ample or compound. 
Simple Leaves are thofe of which the foot-ftalk or 
petiole fupports but one, compound are thofe of 
which the foot-ftalk fuftains many Leaves or fmall 
foiiola. 
Simple Leaves differ in refped to circumfcription, 
angles, fmus, apices, margin, fuperficies and fub- 
ffance ; circumfcription conftders the form of the cir- 
cumference of Leaves where there are no angles or 
finuations ; in which relpeft Leaves are, 
Grbiculate, or round Leaves ( Orbiculatum ) are fuch 
whofe breadth are equal to their length, and every 
part of their edges equally diftant from the center, as 
in fig. i. 
A roundifh Leaf ( Subroiundum ) when the Leaf is nearly 
orbiculate, as in fig. 2. 
An oval or egg-fhaped Leaf ( Ovatum ) when the length 
of the Leaf exceeds the breadth, and the bafe or lower 
part of it forms a fegment of a circle •, but the upper 
extremity is not in proportion, but fmaller, as in 
fig- 3- 
An obvcrfe oval Leaf is one whofe foot-ftalk is fixed 
to its fmaller end. 
An oval or elliptic Leaf ( Ovale five ellipticum ) is one 
whofe length exceeds its breadth, and both ends are 
narrower than tjie figments of circles, as fig. 4. 
A parabolical Leaf (Parabolicum) is one whofe length 
exceeds its breadth, and is narrowed from the bale 
upward, fo becomes half egg-fhaped, fig. 5. 
A fpatulated Leaf ( Spatulatum ) is of a roundifh fi- 
gure, but narrow at the bafe, and linearly lengthened, 
fig. 6. 
A wedge-fhaped Leaf ( Cuneiform ) is one whofe length 
exceeds the breadth, and is narrowed to the bafe, 
fig- 7 - 
An oblongLeaf ( Oblongum ) is one whofe length greatly 
exceeds its breadth, and each extremity is narrower 
than a fegment of a circle, fig. 8. 
L E A 
A fpear-ffiaped or fpear-pointed Leaf (. Lanceohtim ) is 
oblong, and grows narrower toward both ends, and 
terminates in a point, fig. 9. 
A linear Leaf {Linear e) is one whofe two Tides run al~ 
moft parallel to each other they are ufuaiiy narrow, 
and lbmewhat broader in the middle than at the two 
ends, fig. 10. 
A chaffy Leaf ( Acerofum ) is when the linear Leaf ft ays 
on the tree, and is evergreen, as in the Fir, Yew, ,&c. 
fig 11. 
An awl-fhaped Leaf ( Subulaiurn ) is one which is linear 
below, but gradually contracting towards the top, 
fig. 12. 
A triangular Leaf (Tri angular e) is when the difk is 
furrounded by three prominent angles, fig. 13, 
A quadrangular and quinquangular Leaf, only differ 
from the former in the number of their iides or an- 
gles, fig. 14. 
A deltoide Leaf is one with four angles, of which 
thofe of the extremities are farther diftant from the 
center than thofe of the Tides, fig. 15. 
A round Leaf ( Rotundum ) is one without any ah pies. 
A fmus {or Hollow ) is ufed to cxprcfs thofe openings 
or cavities in Leaves which diftinguifh them into parts. 
A kidney-fhaped Leaf ( Reniforme ) is of a round.ifh fi- 
gure, and hollowed a little at the bafe, but without 
any angles, fig. j6. 
A heart-fhaped Leaf ( Cordatum ) when they are ovate 
and hollowed a little at the bafe, but without any 
angles, fig. 17. 
A moon-fhaped Leaf ( Lunulatum } is a roundifh Leaf 
hollowed at the bafe, with two curvilinear angles in 
form of ficldes, fig. 18. 
An arrow-fhaped Leaf ( Sagittatum ) is one which is 
triangular, and hollowed at the bafe for the infertion 
of the foot-ftalk, fig. 19. 
A heart arrow-fhaped Leaf ( CordatumfagittatumfSs , like 
the former, but the fides of it are convex, fig. 20. 
A lpear-pointed Leaf ( Haftatum ) is of a triangular form, 
the fides and bafe of which are hollowed, and the an- 
gles fpreading fo as to refemble a Leaf compofed of 
three parts, fig. 21. 
A fiddle-fhaped Leaf {Pandura forme ) is oblong, 
larger at both ends than in the middle, the two fides 
being compreffed like the body of a violin, fig. 22. 
A cleft or divided Leaf ( Fijfum ) is divided by linear 
finuations and ftrait margins ; from the number of the 
divifions they are termed a two, three, or many pointed 
leaf, fig. 23. 
A lobated Leaf (. Lobatum ) is one which is divided al- 
moft to the midrib, into parts which ftand diftant from 
each other, and have convex margins according to 
the number of thefe parts •, it is called bilobed, tri- 
lobed, or quadrilobed, &c. fig. 24. 
A handed Leaf ( Palmatum ) is one which is divided 
into feveral longitudinal fegments down to the bafe, 
where they are united, and refemble an open hand, 
fig. 25. 
A. wing-pointed Leaf ( Pinnatifidum ) is one which is 
tranfverfly divided into oblong horizontal divifions, 
fig. 26. 
A lyre-fhaped Leaf ( Lyratum ) is one which is divided 
into tranfverfe fegments, the upper ones being larger 
than the lower, which are farther affinder, fig. 27. 
A laciniated or jagged Leaf ( Laciniatum ) is one whofe 
fides are varioufly divided into jags, which are again 
divided without any order, fig. 28. 
A finuatedLeaf ( Sinuatum ) is one which has many fi- 
nuations on its fides, but is not indented or notched 
on its edges, fig. 29. 
An indented finuated Leaf ( Bentato-fnuaium ) is one 
like the former, but the fide lobes are of a linear 
figure. 
A divided Leaf (_ Partitum ) is one which is divided 
into many parts to the bafe, id as to appear like many 
Leaves till clofely examined. Thefe are called bipar- 
tite, tripartite, &c. according to the number of parts, 
fig- 30. 
An entire Leaf ( Integrum ) is one that is undivided, 
and has fmooth edges. 
4 Apex 
