OUR AMPHIBIOUS PERSICARIAS 205 
period, but on once locating a good colony of Persicarias I have 
sought as often as possible during the various seasons to visit 
the place to note the seasonal variations from spring until late 
in fall, and have found these changes in appearance to be often 
quite remarkable. I have in fact, for some years past had the 
field study of the amphibious smartweeds as one of my principal 
aims in botanizing in various places in the east, middle west and 
even far west, and I have become more and more convinced that 
it presents problems that only the local field botanists will be 
able to solve. 
Between the views of Dr. Greene who maintains that there 
are a considerable number of amphibious Persicarias and Linnaeus 
who at his time had but cne, I have stated that no logical opinion 
could be maintained. Dr. Greene has segregated a number of 
species from what was, for the sake of concealing ignorance, called 
P. amphibium Linn. Regarding the suppression of P. Hartwrightu 
as a species in Robinson and Fernald’s Manual, I may here add to 
what I have already maintained concerning this species, that 
logical consistency would demand the suppression of P. emersum 
as well. Dr. Greene has first described the aquatic phase of the 
latter, and I have since found excellent examples of it at Luray, 
Virginia in 1910, and with the aid of any of the above mentioned 
‘manuals it is absolutely impossible to determine this aquatic 
phase of P. coccineum or P. emerswm as anything, but P. amphi- 
bium, in the common sense of the word, as understood by our 
American botanists. It is a glabrous submerged plant with slimy 
floating foliage, leaves subcordate or rounded, and in the aquatic, 
as well as some narrow leaved forms of the summer terrestrial, 
superficially quite indistinguishable by me from P. mesochora 
Greene. Yet the last named plant in its terrestrial spring and 
sterile phase could not by the merest amateur be confounded for 
either what is called P. amphibia, or, especially from any form is 
P. emersa I have ever seen; for the last never has even the slightest 
trace of herbaceous achrea borders so characteristic of P. Hart- 
wright, whereas P. mesochora has these very markedly and always 
in the spring terrestrial phase. 
Moreover, regarding the plant which I found at Luray in the 
Shenandoah River, as P. coccinea or P. emersa, I also found growing 
with it on the shore the various stages of riparian and terrestrial 
phases of the colony, all on one rootstock, the former in mud and 
