( 5* ) 
LECTURE III. 
The firft eighteen Gaffes, with their Orders, explained, 
A previous knowledge being acquired of 
the feven parts, of Frucltfication, with all their 
variations; the different kinds of Fulcra, and 
modes of Inflorefcence, being well underftood; 
the pupil may proceed to the Claffes. 
A Clafs is the firft and higheft divifion of 
every fyftem. It may be compared to a dic- 
tionary, in which all the words having the 
fame initial letter are arranged together, every 
word may be compared to a genus; the 
claffic character is conftituted from a fingle 
circumftance, as the words are arranged by a 
fingle letter ; this one circumftance muft be 
poifeffed alike by every plant admitted into 
the Clafs, how different foever they may be 
in other refpecls. This fingle character is 
arbitrary, and has been taken from various 
parts of the fructification by different authors; 
fome have chofen the petals, others the fruit } 
Linneus has made choice of the ftamens, and 
E 3 on 
