THE CORRESPONDENCE OF SCHWEINITZ AND TORREY 189 
Lemna minor—you say is common through the U. S. I have 
diligently sought it—& never found it—L. gibba I have here & 
in New Jersey, as well as trisulca & polyrrhiza. It is curious 
that with all possible pains I never succeeded in finding any 
species of Lemna in North Carolina. 
Fedia radiata as described by you perfectly answers the specimens 
Tris 
I find here. But what I called so in North Carolina is very 
different. It grows about two & three feet high—The 
Corolla has not the slightest tinge of blue—the stamina are 
not much exserted & the Leaves semiamplexicaule & always 
deeply and lacerately dentate below; sometimes these in- 
dentures are even auriculately produced. 
versicolor. I felt sincerely obliged to you for the successful 
attempt to put an end to all my vexations concerning this 
Iris—& I gladly assent to your reunion. But when you join 
the prismatica of Pursh & gracilis Bigelow—as the true 
virginica of Linnaeus—which is certainly correct—I except 
from this union my prismatica of North Carolina, which I 
had long suspected not to be the same with Pursh’'s. That 
has a very long greatly flexuose stem, winding to the height 
of five feet, & by no means flowers only in a terminal raceme 
but several lateral branches. 
you unacquainted with the Iris cristata and Iris verna— 
differing extremely in habit & marks—& both equally common 
in N. Carolina, the first on hill sides—& the last (which ap- 
proaches nearer to the lacustris you sent me than the former) 
in burnt woods not in tufts but always separate—& extremely 
. Odoriferous. 
Xyris brevifolia was found this year on the Bushkill by the students 
at Naz[areth] & differs very materially from X. flexuosa Ell.— 
I think you ought not to have united X. caroliniana with that. 
Sisyrinchium. I suspect you have not before you the same species 
which I have called by these names (to which I subjoin a 
third found near the Catawba covering whole meadows—ans- 
wering bermudianum) because you seem to describe the leaves & 
scapes in both species as extremely similar—In mine they 
are uncommonly different—the one answering your descrip- 
tion—the other two not at all. Yours I have probably not 
