1957] 



THE BOTANY OF THE GUAYANA HIGHLAND— PART II 



271 



or obsolete, the awn loosely twisted, 1—1.5 cm long, pale, antrorsely scabrous; 

 palea about half as long as the lemma, a membranaceous, nerveless scale; lodi- 

 cules 2, 0.5-0.8 mm long, thin; stamens 3, anthers 2-2.2 mm long; ovary devel- 

 oped; pedicel of the pedicellate spikelet 3-3.5 mm long, flattened, pilose on the 

 margins, otherwise glabrous or scaberulous; pedicellate spikelet 3.5-5 mm long, 

 prominent; first glume 9-nerved, the median nerve developed, scabrous on the 

 margins toward the tip; second glume slightly shorter than the first, thin, keeled, 

 3 (-5)-nerved, the margins near the tip finely ciliolate; sterile lemma slightly 

 shorter than the glumes, 3-nerved, thin, transparent, finely ciliolate on the mar- 

 gins; fertile lemma 3-3.5 mm long, 1-nerved; palea about three-fourths as long as 

 the lemma, a nerveless scale; lodicules 2, 0.5 mm long; stamens 3, anthers 

 mostly 2 mm long; ovary wanting. 



TYPE: frequent in burnt-over area near east escarpment rim, Serra Tepequem, 

 alt. 1000-1200 m, Terr, do Rio Branco, Brazil, December 4, 1954, Bassett 

 Maguire & Celia K. Maguire 40148; U.S. National Herbarium No. 2,182,180. 



This species superficially resembles Andropogon lateralis (Spr.) Nees. 



Andropogon insolitus Sohns, sp. nov. Figure 9. 



Perennis, caespitosus; culmi erecti, graciles, glabri, 25*50 cm alti; vaginae 

 compressae, valide carinatae, glabrae; ligula brevissima, circiter 1 mm longa; 

 laminae usque ad 25 cm longae, usque ad 2.5 mm latae, omnes glabrae, margini- 

 bus scaberrimae, prope basin supra papilloso-pilosae; inflorescentia coarctata, 

 virgata, 5-15 cm longa; articuli marginibus pilosi, dorso pubescentes; spiculae 

 sessiles 4-4.8 mm longae (saepe 4.2 mm longae); gluma inferior 3-nervis, carinis 

 superne scaberrima; gluma superior 3-nervis; anthoecium inferum nullum; lemma 

 fertile membranaceum, enerve; lodiculae 2; stamina 3; antherae 0.9-1.1 mm longae; 

 spiculae pedicellatae 3-4.7 mm longae, staminatae vel neutrae; lodiculae 2; 

 stamina 3; antherae 1.5 mm longae; pedicelli 1.7-2.2 mm longi, marginibus pilosi. 



Perennial, tufted; culms erect, glabrous, 25-50 cm tall; sheaths mostly di- 

 vergent from the culm, compressed, strongly keeled, 5 or 6 vascular bundles on 

 each side of the keel, glabrous; ligule a membranaceous rim about 1 mm long; 

 blades mostly basal, up to 25 cm long, to 2.5 mm wide, glabrous on both sur- 

 faces, antrorsely scabrous on the margins, strongly keeled toward the base, 

 papillose-pilose on the margins and upper surface at the base, the midrib promi- 

 nent as a line of dried gelatinous matter, especially on the upper surfaces; in- 

 florescence compact, branches aggregated; culms supporting fascicles antrorsely 

 short-strigose below the nodes; fascicles composed of two to several short 

 racemes, partially enclosed in the spathes; rachis -joints short-pilose on the mar- 

 gins, pubescent on the back, a prominent rim of hairs below the sessile spikelet; 

 lower pair of spikelets dissimilar, one sessile, the other pedicellate; sessile 

 spikelet one-flowered, 4-4.8 mm long (mostly 4.2 mm long); first glume strongly 

 flattened, margins inflexed, 3-nerved, the nerves and tip slightly scabrous; 

 second glume keeled, 3-nerved, the laterals sometimes obscure; first floret want- 

 ing; lemma a thin, membranaceous, apparently nerveless scale enclosing the 

 palea and essential organs; lodicules 2; stamens 3, anthers 0.9-1.1 mm long; 

 ovary well-developed; pedicellate spikelet staminate or neuter, 3-4.7 mm long; 

 structure similar to sessile spikelet; lodicules 2; stamens 3, anthers 1.5 mm 

 long; ovary undeveloped; pedicel 1.7-2.2 mm long, long-pilose, especially toward 

 the tip, the hairs about 1-1.5 mm shorter than the spikelet, a prominent rim of 

 hairs below the sessile spikelet. 



TYPE: abundant in morichal 2 km south-southwest of Ciudad Piar, alt. 300 m, 

 Estado Bolivar, Venezuela, May 2, 1955, Bassett Maguire & John J. Wurdack 

 35777; U.S. National Herbarium No. 2,116,112. 



