124 CONTRIBUTIONS FROM THE NATIONAL HEKBAEIUM. 



DESCRIPTION. 



Culms ascending from a decumbent base, becoming spreading and much-branched, 

 somewhat compressed, the line of pubescence sparse or wanting; sheaths densely 



papillose-ciliate, otherwise glabrous; blades 4 to 

 10 em. long. 10 to IS mm. wide. Lanceolate, acu- 

 minate, narrowed to the rounded base, more or 

 less pilose on both surfaces; panicles 5 to 12 cm. 

 long, the few, distant, racemes 0.8 to 2 cm. long. 

 ascending or finally spreading: spikelets 3.6 mm. 

 long, about 1 mm. wide, pointed; first glume 

 scarcely one-third the length of the spikelet, his- 

 pid along the midnerve and margin; second glurne 

 shorter than the sterile lemma, 7-nerved, hispid, 

 the hairs longer toward the summit and margin, 

 the sterile lemma 5-nerved, hispidulous and along 

 Fig. 117.— P, biglandviare. From type Tne mar ? m:? hispid, bearing at either side of the 



midnerve a crateriform gland, these more promi- 

 nent; than in P. pulchellum, the sterile palea nearly 

 as long as its lemma, hispidulous: fruit 2.4 mm. long. 0.7 mm. wide, elliptic, minutely 

 stipirate. 



In the original description of P. biglandulare the margins of the sheaths are de- 

 scribed as "clothed with glands bearing branching hairs." The hairs are found to be 

 simple and arising from papilla?. 



DISTRIBUTION*. 



. Among bushes, mountains of Mexico and Guatemala. 



Mexico: Near Pinabete, Nelson 37S1. 

 Guatemala: Coban, Tuerckheim II 1956. 



Parviglumia. — Plants erect or ascending, usually from a decumbent base; culms 

 slender: sheaths densely ciliate and with a dense ring of pubescence at the 

 summit: ligules less than 0.5 mm. long: blades firm, lanceolate, constricted 

 into a very short petiole-like base, and having a thin, white, cartilaginous 

 margin; panicles light green, with few. compactly flowered branches: spike- 

 lets not over 2 mm. long, obovate, obtuse, glabrous, the first glume usually 

 about one-fifth the length of the spikelet: fruit, except in P. parviglurne, with 

 scattered, appressed, silky hairs. 



Besides the three here given two Brazilian species belong in this group: 

 P. trivhidiachne Doella and P. schiffneri Hack..^ 1 and also P. eonchatum 

 Fourn. c described from a Mexican specimen.^ 



Blades 12 to 16 cm. long. 2 to 3 cm. wide: fruit glabrous 70. P. parviglume. 



Blades not over 10 cm. long nor l.S cm. wide: fruit with 

 scattered silky hairs. 



Blades scabrous on the upper surface, not falcate 6S. P. rirgultorum. 



Blades sparsely hispid on the upper surface, falcate 69. P. schmit:ii. 



»In Mart. Fl. Bras. 2-: 339. pi. 49. 1S77. 



&Denkschr. Math.-Xaturw. Akad. Wiss. Wien 79 : 11. 1906. 



cMex. PL 2: 25. 1SS6. 



tf See P. eonchatum Fourn. page 329. 



