( 5* ) 
on their number and fituation has founded 
his claiTes ; he makes the excellence of the 
claffic character to confift in it's greater or 
lefs approximation to the natural one. The 
claiTes called natural are thofe which contain 
plants agreeing in a variety of circumftances, 
fuch as habit, manner of growth, ufes, and 
fenfible qualities. The graffes are a natural 
clafs ; the compound, the pea-bloom, the 
crofs-form, the umbel! ed, and the verticilled 
plants, are natural claiTes ; fo are the ferns. 
Though fome of Lumens' s claiTes are natural, 
raoft of them are artificial; this, however, is, 
perhaps, of little confequence ; his fyftem has 
opened to our view a diftincl: knowledge of 
every plant that grows ; it has given us a 
clear and ready method of referring an un- 
known plant, i ft, to it's Clafs ; 2d, to it's 
Order; 3d, to it's Genus; 4th, to it's Species; 
and 5th, to it's Varieties. Before we had this 
ingenious fyfeem to guide us to a knowledge 
of the vegetable kingdom, all was confufion. 
Much acutenefs had been difplayed in. the 
inveftigation of plants; but the labours of 
many ingenious men were rendered of little 
ufe from want of arrangement; they claffed 
plants together which had fcarcely any affinity, 
from 
