Ctenium concissum Swallen

Ctenium concissum Swallen, sp. nov
Perennial; culms erect, 35-100 cm. tall, pubescent below the spike; sheaths longer than the internodes, scaberulous, the lower ones becoming shredded with age; ligule membranaceous, 1 mm. long, truncate; blades as much as 30 cm. long, 2-4 mm. wide, flat or becoming subinvolute, acuminate, scaberulous; spike 5-16 cm. long, arcuate or becoming flexuous, the rachis 1.5 mm. wide, scabrous on the back, pubescent on the margins; first glume acute, 2 mm. long; second glume acuminate, 8-9 mm. long, scabrous, the awn slender, ascending or spreading, 3-5 mm. long, scaberulous; first sterile lemma 3 mm. long, glabrous on the back, the margins long-ciliate almost the entire length, the awn straight, 4 mm. long; second sterile lemma 4.5-5 mm. long, glabrous on the back, the margins long-ciliate on the upper half, the awn 10-15 mm. long, flexuous; fertile lemma 4—5 mm. long, the margins ciliate on the upper half, the cilia about 3 mm. long, the awn straight, 3 mm. long; palea of the fertile floret subobtuse, scabrous on the keels, the nerves sometimes excurrent in short awns; reduced upper floret 3 mm. long, with an awn about 1 ram. long.
Perenne; culmi erecti, 35-100 cm. aiti, sub spica pubescentes; vaginae internodiis longiores, scaberulae, inferiores concissae; laminae ad 30 cm. longae, 2-4 mm. latae, acuminatae, scaberulae; spica 5-16 cm. longa, arcuata; gluma prima acuta, 2 mm. longa; gluma secunda acuminata, 8-9 mm. longa, scabra; primum lemma sterile 3 mm. longum, marginibus ciliatus, arista 4 mm. longa; secundum lemma sterile 4.5-5 mm. longum, marginibus in parte superiore ciliatis, arista fle.xuosa, 10-15 mm. longa; lemma fertile 4-5 mm. longa, marginibus in parte superiore ciliatis, arista recta 3 mm. longa; lemma reductum 3 mm. longum, arista 1 mm. longa.
Type collected at Picacho de 014, Province of Cocl^, Panama, alt. 350 to 600 meters, Pillier no. 5065 (U. S. Nat. Herb. no. 715193).
Distribution; Savannas, Cocl^ and Chiriqui provinces, Panama.