INTRODUCTION. 
To the fourth and last Part . 
I have already explained that the delay in 
the completion of this work, was mainly owing 
to the contemporaneous publication of my 
Flora Tellurian a, where I inserted the natu- 
ral classification, main principles of natural 
Botany, and nearly 2000 new or revised Genera 
or Species (under 1225 articles) whereof many 
from North America likewise. I now conclude 
this work like the Fi. Telluriana in 4 parts, 
which will include over 1000 new Species with 
some new Genera, many revised Monographs 
Slc ; but yet this is merely one half of what I 
have ready to publish on our Flora, in order to 
correct the glaring errors and omissions of our 
Botanists. 
Whereas Prof. Torrey has been at last indu- 
ced to undertake a general Flora of North 
America, a task which 1 had suggested to him 
many years ago, I shall delay my future addi- 
tions and corrections until alter his Flora is 
published. I call it his Flora, although he hopes 
that Nuttal and others will help him, because 
he means to insert in it only what he has seen 
and ascertained, according to his own notions 
of Species and Genera, overlooking varieties 
and deviations of specific or generic Types ; an 
error into which he has fallen in common with 
several other Botanists, who have reluctantly 
adopted the natural methods of Botany .—But 
time will rectify these absurd and obsolete no- 
tions, and as we now restore, adopt and value 
the labors, genera and varieties noticed by the 
fathers of correct or natural Botany, Adanson, 
Jussieu, Neeker, Richard, Lam ark &c, those of 
