24 Rhodora [FEBRUARY 
3-7.6 dm. (plerumque 3-4 dm.) altis; vaginis superioribus rubro- 
tinctis, apice suboblique truncato integro nec incrassato cartilagin- 
eoque nec hyalino juventute punctato aetate fusco; spiculis ovatis 
vel lanceolatis, acutis, 7-10 mm. longis, circa 3 mm. latis; squamis 
ovato- vel obvato-oblongis, obtusis, 2.5-3 mm. longis, superne castan- 
eis vel fusco-rubris, costa viridescente, apice et margine angusto 
hyalinis; setis 3-4(—5), retrorse barbatis, acheniis paullo vel etiam 
dimidio brevioribus stylis trifidis; acheniis 1.7-2 mm. longis (tuberculo 
incluso), cirea 1 mm. latis, obtuse triangulatis, obovoideis, luteis, 
levissime reticulato-rugulosis postquam squamae decidunt persisten- 
tibus; tuberculis griseis pyramidalibus, acutis, 0.4-0.5 mm. altis, equal- 
iter vel paullo minus latis, ab acheniis evidenter distinctis, basi quam - 
punctus insertionis latioribus. 
Perennial; rootstock creeping, about 2 mm. in diameter, beset with 
sheathing, herbaceous, striate, long acuminate, dark red scales; culms 
clustered, subterete or, at least in dried specimens, slightly compressed 
and somewhat elliptic in cross-section, striate, slender (0.5-1.1 mm. 
in diameter at the summit of the upper sheaths), 3-7.6 dm., averaging 
3-4 dm., tall; upper sheaths tinged with red, subobliquely truncate 
at summit, the margin there entire, not thickened and cartilagin- 
ous nor hyaline, finely red-punctate when young, dark in age; spike- 
lets ovate or lanceolate, acute, 7-10 mm. long, about 3 mm. broad; 
scales ovate- or obovate-oblong, obtuse, 2.5-3 mm. long, castaneous 
or dark red above with green mid-rib and narrow hyaline apex 
and margin; styles three-parted; bristles present, 3—4(-5), downward- 
ly barbed, half as long as the achene or only a little shorter; achenes 
1.7-2 mm. long (tubercle included), about 1 mm. broad, obtusely 
triangular, obovoid, yellow, very slightly reticulate-roughened by the 
raised walls of the epidermal cells, persistent after the fall of the scales; 
tudercles gray, pyramidal, acute, 0.4—0.5 mm. high, about as broad or 
a little narrower, evidently distinct from the body of the achene, 
the base wider than the point of attachment so that the lateral por- 
tions, especially at the angles, are free—Massacuusetts: fresh and 
barckish springy border of Dinah's Pond, Yarmouth, Aug. 16, 1919, 
Fernald & Long, no. 18,025. 
A somewhat puzzling plant. It has the aspect and entire sheaths of 
the group of E. palustris, but is at once distinguished therefrom by its 
three-parted styles and bluntly trigonous achenes. It combines some 
of the characters of E. capitata (E. tenuis) and of E. arenicola, but 
differs from the former in its much smoother achenes and in the reg- 
ular presence of bristles, from the latter in that the achenes are per- 
sistent after the fall of the scales, and from both in the larger size 
of the achenes and the entire sheaths. E. arenicola is apparently its 
nearest relative—one of the many cases in which a southern type 
reappears on Cape Cod. 
