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98 FIELDIANA: BOTANY, VOLUME 28
Lamina of leaf deep green above, glaucous-silvery below.
Type in herb. Chi. Nat. Hist. Mus., collected in dwarf wet woods,
lower southeastern slopes of Carrao-tepui, state of Bolivar, December
5-6, 1944, Julian A. Steyermark 60863. Another collection,
with more juvenile foliage, is same locality, Steyermark 60864.
This species, its leaves with numerous, closely spaced, subeqttal
nerves, is related to P. duidae Steyerm., described above, from
which it differs in the glaucous-silvery lower leaf surface of the
blades, which in a mature stage (Steyermark 60863) have the postical
lobes divided all the way to the petiole. In juvenile leaves (Steyermark
60864) a subpeltate condition is found. In addition, the blades
are relatively narrower, being ovate-oblong instead of ovate-sub-,
orbicular, as in P duidae, and more abruptly acuminate at apex.
Philodendron Krauseanum Steyermark, sp. nov.
Caudex scandens, teres, internodiis superioribus 8-12 mm. longis;
foliorum petiolo 6-11 cm. longo, vagina persistenti latiuscula, ad 17
mm. lata. apice obtusa, laminae basin haud attingenti instructo;
lamina coriacea, oblongo-elliptica, apice cuspidato-acuminata, basi
obtusa vel rotundata, 15-22 cm. longa, 6-8 cm. lata, nervis primariis
utrinque 8, supra conspicuoribus arcuatim adscendentibus; pedunculo
ca. 3.5 cm. longo; spatha extus viridi, 11-12.5 cm. longa, tubo
ovoideo-oblongo, 2.5-3 cm. lato, quam lamina oblonga apice abrupte
cuspidata paullum breviore; spadice cylindrico sursum paullum
attenuate obtuso quam spatha breviore vel longiore, 10.5-16.5 cm.
longo, 1-1.5 cm. crasso; inflorescentia foeminea, 5-7.5 cm. longa,
ca. 1.5 cm. crassa; pistillo prismatico, 5 mm. longo, plerumque
4-loculari, ovulis pro loculo numerosissimis biseriatis, stigmate
majusculo rotundato corona to; inflorescentia mascula 8-9 cm. longa,
1 cm. crassa; floribus masculis prismaticis.
Leaf sheath broad on both sides of petiole and extending to within
7-8 mm. of junction with blade and petiole, slightly produced beyond
the insertion; leaf blades deep or rich green above, dull paler green
below, midnerve prominent, especially below, 1.5 mm. wide, the 8
primary nerves on each side on lower surface of blade much more
conspicuous than the fine, closely spaced, arcuate-ascending
secondary and tertiary nerves.
Type in herb. Chi. Nat. Hist. Mus., collected in lower portion of
Quebrada O-paru-ma', tributary of Rib Pacairao, below Santa Tereska
de Kavanayen, state of Bolivar, alt. 915-1065 m., November 25, 1944,
Julian A. Steyermark 60567. Also collected along wooded quebrada,
Gran Sabana, between waterfall at Rue'-meru (tributary of Rio Kukena'n)
and Divina Pastora on Rio Kukenan north of Santa Elena, south
of Mount Roraima, state of Bolivar, alt. 1065 m., October 3, 1944,
Steyermark 59276.
In the broad petiolar sheath this species approaches P. lingulatum
(L.) C. Koch of the West Indies, but that has the leaf blades more