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BOTANICAL EXPLORATION IN VENEZUELA - I 119
cally to the base, hyaline, elliptic-falcate, more or less navicular,
2.6-2.8 mm. long, about 0.6 mm. wide, acute, rather densely appressed-pilose
on the back, not bearded, not glanduliferous; petals 3,
separate to the base, narrow-elliptic, hyaline, about 1.8 mm. long,
long-attenuate at the apex, the attenuate subcaudate apex involute,
glabrous throughout, not bearded, not glanduliferous; style about
0.5 mm. long, glabrous; ovary oblong, 3-celled, about 0.4 mm. long;
style-appendages 3, about 1 mm. long, erect, arising from a lower
level than the 3 much shorter papillose stigmas.
Type in herb. New York Botanical Garden, collected in
Brocchinia-Stegolepis-Heliamphora swamp, on southwest-facing
shoulder of Ptari-tepui' state of Bolivar, alt. 2200 m., November
2, 1944, Julian A. Steyermark 59779. This handsome species does
not closely resemble any other species of this genus from northern
South America.
Leiothrix umbratilis Moldenke, sp. nov.
Herba; caulibus valde abbreviatis; foliis rosulatis rectis 19-22
cm. longis, 10-13 mm. latis utrinque plusminusve pilosis obtusis, in
statu senectute glabrescentibus; vaginis laxis 14-15 cm. longis
dense patenteque villosis, laminis irregulariter lobatis; pedunculis
7-10, 35-40 cm. longis, sparse pilosulis dein glabrescentibus, ad
apicem persistenter patento-puberulis, 2-costatis compressis tortis.
Herb; stems greatly abbreviated; leaves all basal, cespitose, erect,
thin-chartaceous, grass-green, 19-22 cm. long, 10-13 mm. wide at the
mid-point, rather firm-textured, not fenestrate, more or less pilose on
both surfaces, glabrescent in age, blunt at apex; sheath slightly
shorter than the leaves, cylindric, rather loose, 14-15 cm. long,
densely spreading-villous, obliquely split at the apex, the blade
elongate, erect, usually about 2 cm. long, more or less appressed to
the peduncle, irregularly lobed at the apex; peduncles 7-10 per plant,
35-40 cm. long, very sparsely pilosulous when young, soon glabrescent
except for the very apex which is persistently spreadingpuberulent,
2-costate, flattened, twisted; heads hemispheric, about
1 cm. wide, white, very hairy; involucral bractlets stramineous,
densely imbricate, in many series, variable in shape, oblong or
oblanceolate or elliptic, about 4 mm. long, blunt, about 1 mm. wide,
more or less sparsely pilose on the back, more densely so on the
margins and at the apex; receptacle densely long-villous; receptacular
bractlets hyaline, spatulate, about 5 mm. long and 1 mm. wide,
obtuse, very sparsely pilose near the margins and apex; staminate
florets pedicellate: sepals 3, hyaline, narrow-elliptic, 2.1-2.3 mm.
long, about 0.6 mm. wide, subacute, glabrous throughout or very
sparsely pilosulous at the apex, not bearded, not glanduliferous;
petals 3, hyaline, united into a slender tube about 2.1 mm. long,
glabrous, the free lobes narrow-oblong, hyaline, erect, about 2.1 mm.
l n g glabrous, not bearded, not glanduliferous, somewhat involute
at the apex; stamens 3, included; filaments about 0.4 mm. long;