PANKE.E. 89 



axis thin, wavy involute, 0.5-0.7 mm. Avide. Spikelets 1.4 mm. 

 long on pedicels 1 mm. long, in two rows (one of each pair abor- 

 tive), obovate, subacute, puberulous on tlie margins of the couvo 

 side, first and second glumes thin, 3-nurved. 

 Mexico, I'rinijle 'IVi'd. 



11. P. inops N'asey. ined. 



Culms low, spreading, 10-20 cm. high. Slioatlis hairy, the 

 upper one reaching nearly to the lowest spike, blades Hat, pubescent 

 on both sides, acute, 1-4 cm. long, 4-0 mm. wide. Sjjikes 2-3, 

 1-2 cm. long. Spikelets mostly in pairs, smooth, lu-arly heiui- 

 spbeiical, 2.5 mm. long, iirst and second glumes 5-nervcd, third 

 and the palea brown. 



Mexico (Jalisco), /'afiiirr G17. 



\'ar. major Vasey, ined. Leaf-blades sparingly pubescent, 

 often 15 cm. long, 1 cm. wide; spikes 3-4 cm. long. 



Mexico, /'riiii/h- 1875. 



12. P. conjugatum Herg. Act. llelv. 7. /. 8: 12!» (1772). 

 Chdms brandling, 4-7 cu). high from a cree])ing rhizome. 



Leaf-bhides Hat, acuminate, nearly smooth, 4-10 cm. long, 5-8 mm. 

 wide. Si)ikes 2, sleniUir, exserted, cuhns digitate, sometimes with 

 1-2 lateral ones, 4-15 cm. long, 1.7 mm. wide. Spikelets secund, 

 in two rows, slightly imbricated, ovate, broadly acute. 1.7 mm. 

 long, first and second glunu\s thin, 2-nerved, the first ciliatc on the 

 margins. 



Mexico, J\ihuer 3(i7. PriiKjlo 3129; Alabama, Mohr. 



Florida to Texas and Mexico. 



13. P. tenellum Willd. Enum. llort. Berol. 1:81) (1800). 

 /'. eh'iians Fliigge. Monog. 183 (1810). 



Culms rather slender. GO-!H) cm. high. Sheaths compressed, 

 tlie lower ciliate at the throat; ligule 1-2 mm. long, blades of 

 sterile shoots condu|)licate. 4-10 cm. long. .5-8 mm. wide, acute, 

 imborulent above, those of the culm 1-2 cm. long. Panicle 15-30 

 "Ml. long. Spikes 0-13, the lower 5-15 cm. long, those above 

 gradually growing shorter, rachis slightly flexuose, 0.7 mm. wide, 

 pMbescent at the base and very sparingly along the sides. Spikelets 

 loosely arrangetl in about four rows, some of them on pedicels 



