486 



GONTKIBUTIONS FROM THE NATIONAL HERBAEIUM. 



VIEGATA. 



Perennials, mostly with stout rootstocks, one species, P. ichnanthoides found to be 

 without rootstocks. 



Creeping rootstocks wanting 40. P. ichnanthoides. 



Creeping rootstocks present. 



Spikelets not over 2 . 5 mm . long ; first glume less than half the 

 length of the spikelet. 

 Panicles loosely flowered; first glume truncate, about 



one-fifth the length of the spikelet 37. P: repens. 



Panicles rather densely flowered; first glume triangular, 



about one-third the length of the spikelet 38. P. gouini. 



Spikelets 3 to 7 mm. long (sometimes less than 3 mm. in P. 

 virgatum cubense) ; first glume more than half the length 

 of the spikelet. 

 Culms decumbent or creeping at base. 



n ^ / ff- • Spikelets 3.2 to 4 mm. long 41. P. altum. 



OK i^<,i*vCl8W<^ Spikelets 6 to 8 mm. long 42. P.havardii. 



Culms erect. 



Panicles elongate, strongly contracted; seacoast 



plants 43. P. amarulum. 



Panicles diffuse or only slightly contracted; plants 

 sometimes of salt marshes but not littoral. 

 Panicles open, loosely-flowered ; spikelets 3 .5 to 

 5 mm. long, beaked; first glume two- 

 thirds the length of the spikelet or more, 



acuminate-pointed 39. P. virgatum. 



Panicles somewhat contracted; spikelets not 

 over 3.2 mm. long, not beaked; first 

 glume about half the length of the spike- 

 let, not acuminate 39a. P. virgatum 



cubense. 

 37. Panicum repens L. 



Panimm repens L. Sp. PI. ed. 2. 87. 1762; Contr. U. S. Nat. Herb. 16: 85. 1910. 



DISTRIBUTION. 



Sea beaches, warmer regions of both 

 hemispheres; in America from Ala- 

 bama to Brazil. Originallj^ described 

 from the Old World. 



Nicaragua: Without locality, 

 Flint 8. 



Cuba: AiToyo Apolo, Leoji 296, 

 663. Habana, Le6n in 1909. 



Fig. 51. — Distribution of P. repens. 



