* 
240 PITTONIA. 
and the Carolinas to Labrador and the Lakes had already 
been quite well worked up, though the results were stored 
away in various local floras, or earlier and incomplete general 
treatises. But hitherto, upon the vegetation of the far and 
vast north west, embracing what are now the enormous States 
and Territories of Nebraska, Wyoming, Colorado, Utah and 
Nevada, Idaho, Montana, and almost all of California, Oregon 
and Washington, very few pages had been printed, almost 
nothing was known. But there was just now on hand, and 
ready for the press, a truly magnificent pile of manuscript 
upon the botany of these least known and almost untraveled 
leagues of our domain ; descriptions of new genera of plants 
almost by the seore, and of new species amounting to many 
hundreds, the material of which the author himself had 
gathered upon an expedition at once the most extensive, toil- 
some, perilous and successful which has ever been made in 
the interests of North American botany. I scarcely need say 
that the explorer of those all but impenetrable wilds, and the 
author of these priceless written contributions, now in 1838 - 
ready to be given to the world, was Thomas Nuttall. 
Upon the seven hundred pages of the first volume of the 
Torrey and Gray Flora there are published some four hundred 
and fifty-five new species of plants, an average of about one 
and one-third to each leaf of the book. It is a very large 
percentage of novelties for the Flora of a country, so great a 
part of whose territory had then been under unremitting 
phytographieal investigation for at least a hundred years; 
and it is this fact that the book contains the original deserip- 
tions of almost half a thousand new species, including the 
usual proportion of new generic types, which gives to this 
first volume that kind of a value which never can depreciate. . 
After writers upon genera and species always feel that they 
must, if possible, consult original descriptions. Be these, as 
one too often finds them, too brief, seemingly incomplete, or 
faulty in any way, it still remains that no altered, amended or 
even Improved descriptions of subsequent authors can take 
the place of them in the eye of a critical and accurate phy- 
