20 
INTRODUCTION. 
period would not even listen to it. Correa 
alone began to give lectures on it towards 1816, 
I vainly tried to introduce it in 1817. Pursh, 
Elliot, Torrey, Nuttall, Eaton, Bigelow, &c. 
all wrote their works on the sexual plan. Ha- 
ton alone added thereto the orders of Jussieu 
to his manual : yet he was amazed when Tor- 
rey published his edition of Lindley ! Since 
he and Hooker have begun to open the path in 
England, Beck and Torrey have begun to fol- 
low, while a few others begin to incline to- 
wards it : yet Adanson had disclosed it since 
1763, and Robin Flora of Louisiana used it in 
1807. 
Its progress will be slow here, because it re- 
quires application and study, and my improve- 
ments require besides accuracy and perspicui- 
ty. It will be easier to follow the blunders of 
Lindley as formerly those of Linneus without 
investigation. My own labors on families and 
genera will perhaps meet the fate of those of 
Adanson and Necker, and be denied belief or 
assent for half a century like theirs; but the 
time will come at last to grant me justice, and 
admit me among the classical improvers of the 
science. 
Jealousy of my great labors and discoveries 
may influence some ; but I hope that real Bo- 
tanists ought always to be impartial. Torrey 
is my friend, although we differ in our views of 
Genera and Species, Nuttall has done so much 
already and has so much yet to bring forth 
from Origon, that he need not be jealous of my 
labors. Many other Botanists profess to value 
them. I know of no one that is my avowed foe 
like Dr. Harlan is for Zoology — I have been 
liberal and friendly to all, if they do not reel- 
