150 GLEASON: A NEW GENUS OF RAPATEACEAE 
The flowers become 7-8 mm. long at maturity and are sub- 
tended and almost enclosed by nine to twelve smooth brownish- 
yellow bracts. Of these, the lowest is the smallest and is long- 
acuminate into a slender subulate tip; the second is abruptly 
acuminate into a short tip, while the upper ones are obtuse or 
barely acute and somewhat thickened at the apex. Their shape 
also changes progressively, the outer being lanceolate, the middle 
elliptic, and the innermost oblong-obovate. Their size ranges 
from 3 to 5 mm. long by I-2 mm. wide. 
When the bracts have been removed one by one, the three 
sepals are finally exposed. They are similar to the bracts in 
color and texture, ovate-lanceolate, acute, 5-6 mm. long, 2 mm. 
wide, and closely rolled together after anthesis. 
KG6rnicke noted the great rarity of expanded corollas in all 
the dried material of this family. Among the scores or even 
hundreds of growing plants of Spathanthus unilateralis and 
Rapatea paludosa observed by the writer in British Guiana, 
only one exhibited an open corolla, and on fifty or more fertile 
plants of Windsorina not one open corolla was noted. It is 
probable that the family in general is characterized by a short 
period of anthesis, the petals expanding quickly, remaining open 
for a short time only, and then wilting and contracting back 
into the calyx. Dissections of unopened buds show three yellow 
triangular-ovate petals with basal colorless claws, the whole 
about equaling the sepals. After anthesis, the claw is found to be 
considerably longer and the limb is recurved, more or less 
contorted, and faded to brown. Unopened stamens have short, 
colorless, flat, ovate-oblong filaments less than 1 mm. long, 
which after anthesis are 5-6 mm. long and greatly contorted 
into several folds or loops. The anthers are yellow, lanceolate 
in outline, about 3 mm. long, and quadrilocular, the two inner 
loculi extending only about three-fifths of the distance to the 
apex, above which point the anther is conspicuously narrower. 
It opens by a small pore on the inner surface just below the 
apex. This becomes visible only after anthesis, when the whole 
anther is shriveled and the empty pollen-sacs bright reddish 
rown. 
The structure of the anthers is of considerable taxonomic 
importance in the Rapateaceae. In Cephalostemon and Saxo- 
Fridericia they open by a terminal longitudinal cleft, in Schoeno- 
