Tree 
OUR AMPHIBIOUS PERSICARIAS 243 
foliage becoming somewhat scabrous on the margins. A good 
: example is P. A. Rydberg’s No. (1793) Grant Co., 3 miles NW. 
of Whitman, Nebraska, IX. 20, 1893. There is a duplicate in the 
Herbarium of the New York Botanical Garden. It may not exactly 
coincide in degree of pubescence in aquatic habit with the specimen 
in the U. S. National Herbarium, and I have not had occasion to 
compare them The lower part of this plant is plainly what may 
be considered as the aquatic phase of P. nebrascensis Greene. ‘This 
specimen was collected the same day at the same place by the 
— se SC CU 
collector, as the plant which Dr. Greene made the type of the 
provisional species. A better or rather more aquatic plant may 
be looked for than the specimen of Dr. Rydberg, but its lower 
foliage is unmistakeably aquatic, though the rest of the plant seems 
to have taken on subriparian habit. Dr. Greene in some way seems 
to have overlooked this specimen which with its foliage like that 
of P. ammophila and P. canadensis, and the habit of the former 
plainly shows it to be in every way a very close ally to it in all it 
phases. 
Another plant in the U. S. Nat. Herb. that may be referred 
fe ruere’ 1s. No. 210177, P..:A. Rydbere’s: (1653), VILLI... 7, 1893; 
from the same place as 1793. In the N. Y. Botanical Garden 
Herb. are the following specimens of P. nebrascensvs. 
C. E. Bessey’s from Ames, Iowa. The plant has its lower 
leaves aquatic. J. M. Bates’, Valentine, Neb., IX. 1, 1891. R. I. 
Cratty’s, Emmet Co., Iowa, XII., 1880. A good riparian phase 
with aquatic leaves below and transitional and terrestrial below. 
PERSICARIA HARTWRIGHTI (A. Gray) Greene, 1904 Leaflets, 
Mol. 1.5 p:-24. 
Polygonum Hartwrightti, A. Gray, (1870) Am. Acad. VIII. 
p. 294, including Persicaria abscissa Greene, 1905, Leaflets, Vol. 
i, (p.108: 
The following specimens of typical plants of this species 
may be referred to: 
U. S. Nat. Herb. No. 593949, O. A. Farewell’s, Keweenaw Co., 
VIII., 1904. 
N. Y. Botanical Garden Herbarium: ‘Torrey Herbarium. 
Oates, Ipswich, Mass. (Leaves about 10 cm. long elliptic oblong 
with spreading ochrea borders. A good example of the aquatic 
