OUR AMPHIBIOUS PERSICARIAS 13 
with their own specimens are quick to see that they differ from ours. 
If we consider that Dr. Gray may as likely as not have seen 
the terrestrial phase of the old world P. amphibia, we can see that 
in comparing it with P. Hartwrightvi he must have found sufficient 
reasons for considering it a new species, even if he only saw the 
terrestrial stage of the latter. Its aquatic phase was, as far as 
‘I have been able to find, not known until discovered by Mr. L. 
Andrews in New England. As the Old world plant according to 
Dr. Greene has its separate and distinctly different aquatic as 
well as terrestrial phases we want something more than a mere 
jumping at unwarranted conclusions on the part of some American 
botanists before we can be blamed for not believing that P. Hart- 
wrighttt can be developed at will from P. amphibia by changing 
its habitat, or before we can feel that the most conservative Dr. 
Gray should have published P. Hartwrightti as a new species with 
insufficient reasons. 
Having spent so much of this discussion of the American 
botanists’ view of these plants,—a more or less theoretical aspect— 
I shall now pass to the study of the plants themselves as distributed 
in our locality. In enumerating the plants I shall include first the 
synonymy of the European P. amphibia, even though it is not 
found in our country. I shall trace particularly its pre-Linnaean 
history, aware of the fact that it is not as difficult a matter to give 
its synonymy since 1753. 
As far as I am able to find no one has as yet suggested 
putting the amphibious Persicarias in a separate genus. They 
certainly seem distinctive enough to deserve being gathered 
together as a special group in the genus Persicaria. 
Rafinesque had suggested the genus (or subgenus) Chulusiwm 
for those species ‘ with unequal calyx, five stamens, two stigmas and 
a lenticular seed.’ He mentions this in reference to P. punctatum (?) 
and as the characters are either inconstant or not applicable to 
the amphibious solely and distinctively, I doubt whether the name 
could rightly be applied them. Though no type is mentioned 
P. punctatum would be considered such were the name ever taken 
up for so peculiar a group, because that is the species under which 
the publication of Chulustum is made. Moreover, it does not 
seem clear just what P. punctatum Raf. really is, and this makes 
the publication of the genus even a matter of some uncertainty. 
