HITCHCOCK GRASSES OF CUBA. 215 



Paniclesmalian<l few-flowered, usually 

 about 5 cm. long; blades usually 5 



to 8 mm. wide 12. /'. divaricatum. 



Stems herbaceous. 



Fruit transversely rugose 25. P. maxim u //< . 



Fruit smooth. (See continuation 1.) 

 (Continuation 1.) 

 Plants forming a rosette of basal leaves in autumn ; early culms 

 simple, with terminal, exserted, many-flowered, spreading 

 panicles; freely branching after maturity of primary panicle, 

 and bearing numerous reduced panicles more or less in- 

 cluded in the sheaths. (Dichotomum groui\) 



Ligule a ring of hairs, 1 mm. or more long; spikelets pu- 

 bescent, 1 to 1.5 mm. long. 



Spikelets hardly 1 mm. long; foliage minutely pubes- 

 cent, not velvety 48. P. wrightianum. 



Spikelets 1.5 mm. long. 



Foliage smooth or minutely puberulent 24. P. leucothrix. 



Foliage velvety 1 . P. acuminatum. 



Ligule inconspicuous. 



Autumnal state a flat mat or rosette of soft leaves; 

 blades ciliate; spikelets 1.5 to 2mm. long, glabrous. 



Blades pilose on the surface 41. P. strigosum . 



Blades glabrous on the surface 33. P. polycaulon. 



Autumnal state erect or spreading. 

 Sheaths velvety or pilose. 



Vernal culms 1 meter or more tall, a viscid 

 ring below each node ; primary panicles 10 

 to 20 cm. long; autumnal blades, 5 mm. 



or more wide 37. /'. scoparium. 



Vernal culms 20 to 40 cm. tall; primary pan- 

 icles 2 to -6 cm. long; autumnal blades 1 to 



2 mm. wide 6. P. chrysopsidifolium. 



Sheaths not velvety nor pilose. 



Culms wiry, minutely crisp-puberulent; 

 spikelets pyriform-turgid. 



Spikelets L.5 mm. long 31. P. pauciciliahim . 



Spikelets 2 mm. long 22. P. lancearium. 



Culms glabrous, or only lowermost internodes 

 pubescent. 



Spikelets glabrous, 1.6 mm. long 7. P. caerulescens. 



Spikelets pubescent. 



Nodes bearded; spikelets 2 mm. 



lung . 28. P. nilidum. 



Nodes glabrous or pubescent, not 

 bearded. 

 Blades long and narrow, autum- 

 nal blades involute; spikelets 

 papillose. 



Spikelets 2 mm. long, blunt .27. /'. neuranthum. 

 Spikelets about 3.5 mm. 



long, pointed 16. P./usifoi~me. 



Blades not elongated , autumnal 

 blades flat; spikelets not pap- 

 illose. 



