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. Ea- 

 ton alone added thereto the orders of Jussieu 

 to his manual ; yet he was amazed when Tor- 

 rey pubhshed his edition of liindley ! 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 

 liindley 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 reci- 



