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BOTANICAL EXPLORATION IN VENEZUELA - I 109
longitudinally nerved, whereas in X, lugubris they are impressednerved
with numerous conspicuous pale puncticulate stomata, the
ligules of the sheaths not lacerate, and the bracts of the heads less
conspicuously lacerate on the margins.
Xyris esmeraldae Steyermark, sp. nov.
Caespitosa subbulbosa, aphylla vel folia obsoleta; scapis numerosis
tenuibus, subteretibus, valde spiraliter tortis, 12-20 cm. altis,
0.5 mm. latis, omnino glabris; spicis ellipticis vel fusiformibus,
4-4.5 mm. longis, 1-1.5 mm. latis; bracteis 2 infimis late oblongis
vel ovato-oblongis, obtusis, 2 mm. longis, 1 mm. latis, marginibus
scariosis, ceteris ad 3.5 mm. longis, ad 4 mm. latis; sepalis lateralibus
lance olatis, 3 mm. longis, 1 mm. latis, apice denudatis, ala
carinali parce denticulata; capsula uniloculari, 3-valva.
Plant semi-bulbous at base; leaves reduced to short bracts at base
or absent; seeds at base of capsule on long erect funicles (Fig. I6,c).
Type in herb. Chi. Nat. Hist. Mus., collected in swampy woods
between Esmeralda Savanna and southeastern base of Cerro Duida,
Territorio Federal Amazonas, alt. 200 m., August 22, 1944, Julian
A. Steyermark 57821.
The fact that the specimen is not in flowering condition makes its
exact position in the genus somewhat uncertain, but there is no doubt
but that it
pertains to the subgenus Nematopus Seubert. The possession
of lateral sepals naked at the apex and denticulate on the
keel would place
it
probably in Sect. V. of Malme (X, Hymenachnes)
and, because of its spirally twisted scapes, near X. tortula Mart, and
X. simulans Alb. Nilsson var. subtortula Malme. From these species,
X, esmeraldae may be distinguished by the smaller, narrower spikes,
smaller lateral sepals, conspicuously spirally twisted narrow scapes,
and leafless condition.
Xyris lanulobractea Steyermark, sp. nov.
Caespitosa; foliis erectis subteretibus coriaceis subsetaceis,
apice subulatis, subtiliter striatu latis, omnino glabris, 18-44 cm.
longis, 0.5-1 mm. latis; vagina sextam vel nonam partem folii occupante,
inferne castanea, nitida, eciliata; scapo erecto vel basin
versus paullo torto subtereti subtiliter striatulato, omnino glabro,
40-50 cm. longo,
1 mm. lato; spicis ovato-ellipsoideis vel ovoideis
multifloris, 9-11 mm. longis, 6-7 mm. crassis; bracteis coriaceis,
brunneis praeter apices, infimis parvissimis sterilibus, late oblongis
vel oblongo-suborbicularibus, apice rotundatis, 3-5 mm. longis, 2.5-
3.5 mm. latis, intermediis superioribusque fertilibus, late oblongis
vel rhomboideo-oblongis, 5 mm. longis, 4-4.5 mm. latis, area dorsali
distincta oblonga sub apice obtusa et irregulariter reticulata, supremis
dense longe ciliatis, ceteris pane superiore et apice dense
albido-lanuginosis; sepalis lateralibus liberis, paullo inaequilateris,
obla nee olatis, 5 mm. longis, 0.9-1 mm. latis, apice villosis, ala
carinali in parte quarta superiore dense fimbriato-villosis pilis