up to 13.5 em. long. Pedicels about 1.8 mm. long. Calyx 
2.8-4 mm. long, accrescent, puberulent and sparsely 
glandular-pilose outside, glabrous within, shallowly 4- 
dentate, the teeth apiculate, 1 mm. or less in length. 
Corolla yellowish, up to 3.8 em. long, ampliate above, 
5-lobed, sparsely glandular-pilose outside, sparsely gland- 
ular within with sessile or short-stipitate glands. Sta- 
mens four, didymous, included, the two shorter ones 
about 1.3 cm. long, the two longer ones about 1.7 cm. 
long: filaments glabrous; staminodium linear-clavate, 
glandular-lepidote. Ovary glabrous, 2-celled, with axil- 
lary placentae and numerous ovules. Style filiform, about 
2.6 cm. long, glabrous, shallowly bifid, the stigmatic 
lobes unequal, the shortest one erect. 
SPECIMENS EXAMINED: 
Mexico: Tabasco, on limestone rocks at Retiro, near ‘lenosique, 
June 19-25, 1939, Fist Matuda 3425 (Tyre in Herb. Univ. Michigan; 
Isorvee in Econ. Herb. Oakes Ames No. 7113). 
Uroskinnera flavida is easily distinguished from the 
other known species of the genus by its yellow rather 
than rose-purple flowers, by its membranaceous rather 
than chartaceous leaves, and by its puberulent, not seri- 
ceous, indument. Florally, U. flavida differs strikingly 
from the other species in having a staminodium which 
is longer than the fertile stamens. 
The long and lax inflorescence of Uroskinnera flavida 
resembles somewhat that of U.hirtiflora, but it is entirely 
unlike the short, crowded inflorescences of the two Gua- 
temalan species. In U.flavida, the calyx and floral bracts 
are puberulent, while in the other species these structures 
are densely hirsute. The glandular-lepidote corolla of U. 
flavida, which resembles the hirsute corolla of U. hirtiflora, 
is unlike the glabrous corollas of U.spectabilis and U. 
Watsoni. 
While Uroskinnera flavida is obviously closely related 
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