490 PROCEEDINGS OF THE AMERICAN ACADEMY. 
Manual it is given only minor recognition, as a probable form of 2 
‘“‘ovata,’ and in the Illustrated Flora it is not even mentioned. Though 
the plant is as yet known only from a limited area in the Connecticut 
valley, its structural characters distinguish it from Z. ovata and £. obtusa 
quite as clearly as do those of the now well recognized Z. Engelmanni. 
An Arkansas plant (Figs. 27 to 29) sent by Prof. F. L. Harvey to 
the late William Boott has been passing as a form of Z. obtusa. In 
habit the plant resembles both that species and Z. diandra, but its cap- 
illary culms are as fine as in the most slender specimens of the latter 
species. The heads, however, are not broad as in those species, but 
lanceolate and acute, 5 to 8 mm. long. The very pale ascending scales 
are lanceolate or oblong-lanceolate and acuminate. The achene, though 
not unlike that in the smallest form of Z. obtusa, is shorter and broader 
than is usual in that plant, and the tubercle is hardly so depressed. 
Another plant (Figs. 45 to 52) which has been included in the com- 
plex called Eleocharis ovata is a low but erect plant of the Northwest, 
occurring from the Cceur d’Alene valley southwestward through Oregon 
to the northern Sierra Nevada of California and extending eastward to 
the northern prairie region. The original specimens sent by Mrs. Pul- 
sifer Ames from the Sierra Nevada in 1876 were referred by Dr. Gray 
to E. palustris, and subsequently by Dr. Watson to &. obtusa. Similar 
specimens, if not from the identical collection, were sent by Mr. Lem- 
mon to William Boott, who pronounced them Z. obtusa, as he did also 4 
plant sent a year later by Mr. Howell from Multnomah Co., Oregon 
Excellent material of essentially the same plant recently distributed by 
the National Herbarium from the Coeur d’Alene valley in Idaho is la- 
belled E. ovata, as are also exceptionally large specimens collected ‘by 
Professor Macoun in Manitoba. Though habitally somewhat suggesting 
the common JZ. obtusa, this’ northwestern annual plant has narrower 
looser-flowered acutish heads varying from ovate-lanceolate to oblong- 
lanceolate, and the narrower chestnut-tinged scales are acutish and more 
spreading. The achenes, though not unlike those of Z. obtusa, are capped 
by more compressed tubercles resembling those of E. Engelmann. The 
bristles, too, are like those of the latter species, about equalling the 
achene or much shorter, not exceeding it as in Z. obtusa. In the sents 
of its spike and tubercle, then, and in its bristles, the northwestero 8 
1s more like Z. Engelmanni than E. obtusa, From that species it differ 
in its more ovoid head, and darker more acutish and spreading scales- 
E. Engelmanni, as ordinarily recognized, is a species of low altitudes, — 
primarily in the middle States, and rarely reaching the Atlantic seabo# 
