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68 FIELDIANA: BOTANY, VOLUME 28
the body widest just below the middle, membranaceous, pale to
silvery green, tapering into a beak about equaling the length of the
body, the beak flat, scabrid from middle to apex; style straight,
slender, jointed with achene, at length deciduous; achene somewhat
narrowed above, yellow-brown (Fig. 7, a-c).
Type in herb. Chi. Nat. Hist. Mus., collected in spongy soil with
dense mats of vegetation in depression of morro, summit of Mount
Roraima, on southern half of the summit between Summit Camp,
Great Central Rift, Central Swamp, and pond at southern end, state
of Bolivar, alt. 2700-2740 m., September 28, 1944, Julian A. Steycrmark
58870.
This species is characterized by the greenish-white perigynia and
scales, perigynia broadest in lower half and relatively narrow
achenes 2 mm. long, culms scabridulous below the heads, poorly
developed sterile culms, and elongated bract of inflorescence. It is
placed here in section Ovales, because of the wing-margined perigynium,
which is not spongy-thickened at base.
This is the second member of the group O vales to be recorded
from South America, C. Longii Mack. (C. albolutescens) being the
other. It is the first of the group belonging to the sections Festucaceae
or Fetae, as treated by Mackenzie in the North American Flora,
to be recorded from South America, since Mackenzie placed C. Longii
in section Alatae.
Although I have not seen the specimen, this is apparently the
plant from the summit of Roraima (lie 8536) reported by Kukenthal,
in Engl. Bot. Jahrb. 56. Beibl. 125: 25 (1921), as C. Bonplandii
Kunth. However, careful study of our material shows that it is not
C. Bonplandii, not even in the section to which that species belongs.
From C. Longii this new species may be distinguished by the narrower
perigynium, not broadest above the middle, the longer beak
and achene. Its elongate bract, together with other characters of the
perigynium, distinguishes it from C. tenera, C normalis, C, moles ta,
and C. feta, all of which it resembles. From the members of the
Athrostachyae and Cyperoideae, in which the bracts are either leaflike
or conspicuously exceed the head, this species differs in the
heads not congested, and either paler-colored scales, or different
shape and size of perigynium. From C. foenea, which has an elongated
bract of the inflorescence, this species differs in having the
sterile culms poorly developed, narrower perigynia, larger achenes,
and beak larger in proportion to the rest of the perigynium.
Carex tachirensis Steyermark, sp. nov.
Plarita caespitosa; culmis in anthesi 3*5-8 cm. altis, in fructu
15 cm. altis, angulis scabridulis 2-bracteatis; foliis erectis, coriaceis,
basi aggregates, linearibus, obtusis, 3-5 cm. longis, 1-1.5 mm. latis,
marginibus et superne per margines partis canaliculatae subtilissime
denseque setulosis evaginantibus; spica simplici androgyna, apice