4 .Rhodora [JANUARY 
2 mm. long, about twice as long as in our other species. The first 
of these, P. maritima, is a plant of the Atlantic coasts of Europe and 
of eastern America (from Cape Breton to Pennsylvania); the second 
an Arctic species which extends southward to Labrador and the 
shores of Hudson Bay. 
The remaining species have conspicuously smaller anthers, 0.5-1 
mm. long, in only one species very slightly exceeding this measurement. 
In some of the plants with small anthers the mature caryopsis (and in 
good specimens of Puccinellia some inflorescences are usually mature 
while others are just expanding) is large, ordinarily more than 2 mm. 
long, while in others the grains are about 1.5 mm. in length. The 
measurements of the mature grain, like the measurements of the 
anthers, prove to be essentially constant in all material which is other- 
wise consistent and we have consequently used this character as an 
important one. Another character of as great importance is found in 
the margin of the lemma; in some species the lemma is entire or with 
at most one or two coarse teeth, while in others it is as definitely erose- 
ciliolate or serrulate. Good characters are also found in the palea, 
especially in the degree of ciliation; and other characters, often less 
readily described and more subject to variation, in the aspect of 
the panicle, the smoothness or hispidity of the rhachis and panicle- 
branches, the length of the glumes, ete. 
The present paper, presenting our conclusions regarding the species 
of Puccinellia in northeastern North America obviously does not cover 
all the species which may possibly be found in the area. This will be 
apparent from the fact that one Arctic species alone, P. phryganodes, 
yet been found on the little-explored Labrador Peninsula, but 
that in Greenland and Arctic America several other distinct species are 
found, P. angustata (R. Br.) Rand & Redfield, P. arctica (Hook),’ 
P. Vahliana (Liebm.) Scribn. & Merrill, ete., any of which may be 
expected to reach the Labrador Peninsula or Newfoundland. Further- 
more, such very limited collecting as has been done at remote points 
about the Gulf of St. Lawrence and the eastern coast of Newfoundland 
has brought together five very distinct plants which are unknown 
elsewhere in the East, and future exploration of the complex flora of 
these areas will doubtless extend the ranges of these plants and pos- 
sibly bring to light other localized species. 
SS an ae arctica (Hook.), n. comb. Glyceria arctica Hook. Fl. Bor. -Am. ii. 
. 229 (1840). 
‘N 
