PREFACE. Xi 



when I consider that the small collection communicated 

 to me, consisting of about one hundred and fifty speci- 

 mens, contained not above a dozen plants well known to 

 me to be natives of North America, the rest being either 

 entirely new or but little known, and among them at 

 least six distinct and new genera. This may give an 

 idea of the discerning eye of their collector, who had 

 but little practical knowledge of the Flora of North 

 America, as also of the richness of those extensive re- 

 gions in new and interesting plants, and other natural 

 productions. 



The descriptions of those plants, as far as the speci- 

 mens were perfect, I have inserted in the present work 

 in their respective places, distinguishing them by the 

 words " V. s. in Herb. Lewis." Several of them I have 

 had an opportunity of examining in their living state, 

 some being cultivated from seeds procured by Mr. Lewis, 

 and others since my arrival in England from seeds and 

 plants iiitroduced by Mr. Nuttall. 



Here I cannot refrain from drawing the attention of 

 future botanists travelling those regions, to two highly 

 interesting plants, of which I have only seen imperfect 

 specimens. The first is what Mr. Lewis in his journal* 

 calls "the Osage Apple," or " Arrowwood of the Mis- 

 souris." This is a tree, or rather shrul), with leaves re- 

 sembling those of a pear-tree, but broader in propor- 

 tion ; they are alternate, and have a recurved thorn near 

 their base ; the flowers are of separate sexes, and appear 

 in axillary, peduncled, globular catkins, which produce 

 a depressed globular fruit, in size and colour resembling 

 an orange, in interior structure approaching near to the 

 genus Morinda. This shrub, on account of its fruit 



