is very scarce and local. But it fills
California and the interior of Oregon quite back to the west slope of
the Rocky Mountains. Fremont mentions it as the first spring food for
his cattle when he reached the western side of the Rocky Mountains. And
hardly anybody will believe me when I declare it an introduced plant. I
daresay it is equally abundant in Spain. I doubt if it is more so.

Engelmann and I have been noting the species truly indigenous here
which, becoming ruderal or campestral, are increasing in the number of
individuals instead of diminishing as the country becomes more settled
and forests removed. The list of our wild plants which have become true
weeds is larger than I had supposed, and these have probably all of them
increased their geographical range--at least, have multiplied in numbers
in the Northern States since settlements.

Some time ago I sent a copy of the first part of my little essay on
the statistics (330/1. "Statistics of the Flora of the Northern U.S."
("Silliman's Journal," XXII. and XXIII.)) of our Northern States plants
to Trubner & Co., 12, Paternoster Row, to be thence posted to you. It
may have been delayed or failed, so I post another from here.

This is only a beginning. Range of species in latitude must next be
tabulated--disjoined species catalogued (i.e. those occurring in
remote and entirely separated areas--e.g. Phryma, Monotropa uniflora,
etc.)--then some of the curious questions you have suggested--the degree
of consanguinity between the related species of our country and other
countries, and the comparative range of species in large and small
genera, etc., etc. Now, is it worth while to go on at this length of
detail? There is no knowing how much space it may cover. Yet, after all,
facts in all their fullness is what is wanted, and those not gathered
to support (or even to test) any foregone conclusions. It will be prosy,
but it may be useful.

Then I have no time properly to revise MSS. and correct oversights. To
my vexation, in my short list of our alpine species I have left out,
in some unaccountable manner, two of the most characteristic--viz.,
Cassiope hypnoides and Loiseleuria procumbens. Please add them on page
28.

There is much to be said about our introduced plants. But now, and for
some time to come, I must be thinking of quite different matters. I mean
to continue this essay in the January number--for which my MSS. must be
ready about the 1st of November.