326 A. Gray— Mora of North America. 



In the Supplement, Pursh was able to include a considerable 

 number of species, collected by Bradbury on the Upper Mis- 

 souri, in what was then called Upper Louisiana, — much to the 

 discontent of Nuttall, who was in that region at the same time, 

 and who, indeed, partly and imperfectly anticipated Pursh in 

 certain cases, through the publication by the Fraser's of a 

 catalogue of some of the plants collected by Nuttall. 



To come now to the extent of Pursh's Flora, published nearly 

 sixty-nine years ago. It contains 740 genera of Phaenogamous 

 . and Filicoid plants, and 3076 species. Just about double the 

 number of species contained in Michaux's Flora of eleven years 



I must omit all mention of more restricted works, even such 

 as Nuttall's Genera of North American Plants, which came 

 only four years after Pursh's Flora; also the Flora Boreali- 

 Americana of Sir Wm. Hooker, which began in 1829, but was 

 restricted to British America. I cannot say how early it was 

 that my revered master, Dr. Torrey, conceived the idea of the 

 Flora which he at length undertook. But he once told me 

 that he had invited Nuttall to join him in the production of 

 such a work, and that Nuttall declined. This must have been 

 as early as the year 1832, that is, half a century ago. My cor- 

 respondence with Dr. Torrey began in the summer of 1830, 

 when I was a young medical student, and three or four years 

 afterward I joined him at New York and became, for a short 

 time, his assistant, for all the rest of his life his botanical 

 colleague. He was very much occupied with his duties as 

 professor, chiefly of chemistry : he had not yet abandoned the 

 idea of completing his Flora of the Northern and Middle 

 States, the first volume of which was finished in 1824, while 

 yet free from all professional cares. Although working in the 

 direction of the larger undertaking, the Flora of North America 

 did not assume definite shape before the year 1835. I believe 

 that some of the first actually-prepared manuscript for it was 

 written by myself in that or the following year. I was then 

 and for a long time expecting to accompany the South Pacific 

 Exploring Expedition, as originally organized under the com- 

 mand of Commodore Ap. Catesby Jones, but which was sub- 

 ject to long delay and many vicissitudes; during which, having 

 plentiful leisure, I tried my 'prentice hand upon some of the 

 earlier natural orders. Before the expedition, as modified, was 

 ready to sail, under the command of Capt. Wilkes, I had 

 accepted Dr. Torrey's proposal that I should be his associate 

 in the work upon which 1 had made a small beginning as a 

 volunteer. Two parts, or half of the first volume (360 pages), 

 of this Flora, were printed and issued in July and October, 

 1838. 



