22 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 98 



tose ; flower-clusters closely crowded on the branches, especially on 

 the lower sections of the basal branches ; basal bract of flower-clusters 

 moderately developed, notably less prominent than the collar bracts ; 

 male flower-scars often oblong quadrate or rounded, margined or 

 winged with tomentum especially on the mesial side, the pedicel 

 reduced to a thin disk, but sometimes distinct ; fruits with an in- 

 durated discoid frustum bearing the persistent indurated style and 

 stigmas ; pericarp granular-tuberculate on the surface, hard and crus- 

 taceous in texture, with irregular granules like stone-cells ; mesocarp 

 fibers flexuous and variable in size, forming a rather irregular net- 

 work ; seed distinctly flattened on the upper face, a broad gradually 

 sloping groove between the hilum and the embryo, and a short, narrow 

 raphe, extending about halfway to the embryo. 



DESCRIPTION OF PLECTIS OWENIANA COOK 5 

 Plates 4, 7, 20-26 



Trunk smooth, ringed with leaf scars, attaining 25 m. in height, 

 68 cm. in circumference at base, 50 cm. at one meter above the base, 

 27.5 cm. at the top ; trunk supported on a conical mass of thick tuber- 

 culate roots 7.5 cm. in circumference, with large fibrous root-caps ; 

 sometimes with aerial roots growing from higher internodes, to a 

 meter above the surface, forming props around the trunk as in the stilt- 

 palms, Iriartea and related genera. The special development of aerial 

 roots may be an adaptive character for growing on massive limestone 

 formations. 



Leaf-sheath bundle 150 cm. long, 27.5 cm. in circumference near 

 the top ; margin of the sheath thin and friable, a projection or antili- 

 gule about 6 cm. long opposite the petiole, of fleshy or membranous 

 texture, not fibrous, fragile when dry, about 6 cm. long, 5 cm. broad. 

 Texture of leaf -sheaths thin, with a delicate lining that separates 

 readily; petiole 37-47 cm. long, nearly 4 cm. wide near the base, 3 cm. 

 below the first pinnae, broadly grooved in the lower part, nearly flat 

 above, the upper surface with scattered minute fugacious scales. 



Rachis 267 cm. to the insertion of last pinna, 27 cm. wide near the 

 base, the upper surface nearly flat, gradually becoming ridged and tri- 

 angular in cross-section, flat underneath, tapering from 8 mm. wide 

 to only 2 mm. near the end, continued as a slender fiber as long as the 

 last pinnae. Surface of rachis with scattered fine scales, larger and 

 more abundant on a small oblique area below the insertion of the pinna 



Bulletin of the Torrey Botanical Club, vol. 31, p. 353, June 1904. 



