The Anatomy Book VL 
CHAP. IIL 
Of the Figure of the Leaf; and the Apparent Pofition of 
the Fibres. 
y HAT which in the Leaf offers it felf next to 
be obferved, is its Figure. This is infinitely va- 
ried with the feveral Kinds of Plants: and there 
are fome, which have Leaves ( befides the two 
firft Diffimilar ones ) of Two Kinds or Two di- 
ftinét Figures; as the Bitter-Sweet, the com- 
Q mon Little Bell, Valerian , ` Lady-Smocks , and 
y others, For the Under Leaves of Bitter-Sweet, 
are Entire; the Upper, with two Zobes : the Under Leaves of the 
Little Bell, like thofe of Pancy; the Upper, like thofe of Carnation, 
or of Sweet-William. And in fome Plants, Nature affe@eth a Kind 
of Irregularity 5 the Leaves whereof are of no one certain Figures as 
in Dragon, Peony, Bifhops-Weed, Exc. 
2. $. BUT the Leaves of molt Plants, have a Regular Figure; 
and this Regularity, both in Length and Circuit, always defineable. 
In Length 5 by the Proportion between the feveral Leaves upon one 
Stalk , or between the feveral Lobes upon one Leaf. So the Leaves 
of Clematis Sylv. major, which ftand by Ternaries, fhorten by equal 
Proportions, that isto fay, if, the chief Fiber of each, be divided into 
equal Parts; their feveral Lengths are not as Ten,Eight,and Four 5 but 
as Ten, Eight, and Six. So the Lobes and Fibers of Clematis Virgini- 
ana Hedere folio, of Artennifa, &c. fhorten in like manner by equal 
Proportions. The fame is obfervable in meafüring, upon a Gooféberry- 
Leaf, from the Poynt of the firft Lobe, to the firlt Angle 5 from thence, 
to the fecond Poynts from thence, to the fecond Angle; and from 
thence to the third Poynt. 
3. §. But in many, the Proportion is different. So in the Leaves 
of the Lefer Maple ; the fhortning of the fmaller Lobes, with refpeĝ to 
the middelmoftz is not Equal, but Double to that of the middlemoft, 
with refpe& to the Greater. For if their chief Fibres be divided into 
Equal Parts, they are as Eleven, Nine, and Five. On the contrary, 
in the Leaves of Althea fiuticofa Pentaphylloidea, the middlemoft Lobes 
fhorten by a greater Proportion than the Leaft; all three being as Ten, 
Fourteen, and Twenty. 
4 $. WITH refpet to the Circumference, the Figure of moft 
Leaves is very Complex. Yet Two things are evident. Firft, that all 
Regular Leaves,are defined or meafured out by Circles 5 that is, by the 
Arches or Segments of feveral Circles, having either the fame, or di- 
vers Centers and Diameters. Secondly, That the Length of the Leaf, 
orofthe chief Fiber thereof, is the Standard Meafure for the Diane 
ters of thefe Circles: thefe being either its full Length, or certain 
equal parts fubftracted, or multiplied; as half itsLength, or its Length 
and half, &c, 
5 $ 
