THE AGRICULTURAL GRASSES OF THE UNITED STATES. 115 



Perfect. Having both stamens and pistils. 

 Petiole. The stem of a leaf. 



Pititil. The central or female organ of a fertile flower. 

 Pistillate. Having only pistils without stamens. 

 Plumose. Feather-like. 



Pollen. The powder contained in the anthers. 



Pubescent. Clothed with short and soft hairs. 



Eadical leaves. Those growing from the base of the culm. * 



Bevolute. Rolling backwards or outwards. - 



EhacMs. The axis or stem on which the flowers of a spikelet are arranged ; also the 



common axis of a close spike or of a panicle. 

 Ehizoma or rootsiock. A horizontal underground stem. 

 Bibs. Prominent nerves of the leaves or glumes. 

 Bugose. Wrinkled or furrowed. 

 Scahrous. Rough, with small points or hairs. 

 Scarious. Dry and thin, and generally transparent. 

 Sericeous. Covered with soft, silky hairs. 



Serrate. Having teeth on the margin, pointed toward the apex. 



Serrulate. Finely-toothed. 



Sessile. Without a foot stalk or pedicel. 



Setaceous. Like a bristle. 



Sheath. That part of the leaf which embraces the culm or stalk. 



Spike. A collection of sessile or nearly sessile flowers on a close, narrow axis. 



Spikelet. A flower or cluster of flowers having one pair of outer glumes. 



Stamen. The male organs of a flower, including the anther and filament. 



Staminate. Having only stamens. 



Sterile. Imperfect flowers not producing seed. 



Strict. Erect and close. 



Stoloniferous. Sending off oftshoots or runners from the base. 

 Strigose. Having spreading, bristly hairs. 

 Subulate. Stiff and linear, shaped like an awl. 

 Succulent. Fleshy and juicy. 



Style. That portion of the pistil bearing stigmas or a stigmatic surface ; in grasses 



often branching. 

 Truncate. Abruptly cut off" at the apex. 

 Unequal. Not of equal length. 

 Verticillate. Arranged in a whorl or whorls. 

 Villous. Velvety, clothed thickly with long, soft hairs. 



Whorl. A number of leaves or branches arranged around a stem on the same plane. 

 Wooly. Clothed with long and matted hairs. 



