22 . . 



Panicle larger, oval, or oblong — Continued. 



47. P. latifolium, Linn. 



48. P. scabriusculura, ML ? Chap. 



Panicle effuse; brandies capillary and m uch subdivided, except in P. 

 sparsiflorum (P. angustifolium Chap., non Ell.): 

 JO. P. capillare, Linn. 



50. P. auturnnale, Bosc. 



51. P. Hallii, Y. <& S. 



52. P. proliferum, Lam. 



53. P. iniliaceum, Linn. 



54. P. verrucosum, 21 uhl. 



55. P. sparsiflorum (P. angustifolium, Chap., non PH.). 

 Tall grasses, with ample and diffuse panicle : 



56. P. anceps., Miclix. 



57. P. agrostoides, Muhl. 



58. P. bulbosum H. B. K. and var. avenaceum. 

 50. P. maximum Jacq. (P. jumentorum, Pers.). 

 GO. P. amarum, Ell. 



Gl. P. virgatuin, Linn. 



62. P. Havardii, Yasey. 



Section VIII. — Frutescentes. — Culms frutescent, spikelets large and 

 tnrgid, empty glumes loose. 



63. P. clivaricatum, Linn. 



Section IX. — Yilliflora. — Panicle diffuse, spikelets very large, the 

 glumes very silky-villose. 



G4. P. Urvilleanum, Kth. 



Section I.— Digitaeia. 



1. P. glabrum, Gaud. (Digitaria humifusa Pers). — Culms spreading, 

 prostrate or erect, 5 to 12 incbes long ; leaves 1 to 2 iucbes long, smootb 

 or pubescent; spikes 2 to G, spreading, 1 to 2 incbes long, approxi- 

 mate; spikelets oblong, about 1 line long, obtusisb; empty glumes, 

 mostly two (tbe lower one generally wanting), pubescent, botb equaling 

 the flower. 



In cultivated and waste grounds less common than the following. 

 Variety Mississippiensis, Gattinger. — Taller (6 to 20 inches high), 

 spikes longer (1J to 3i inches), spikelets acutish. 

 Vicinity of Nashville, Teun. (Dr. Gattinger). 



2. P. saugniuale, Linn. (Crab-grass). — Culm erect or decumbent, 

 usually rooting at the lower joints, leaves and sheaths smooth or hairy, 

 variable in length and breadth; spikes 3 to 10 or 15, spreading, digi- 

 tate or approximate, 3 to G inches long; spikelets oblong-lanceolate, 

 about 1£ Hues long, acute, smoothish, pubescent; first glume minute, 

 second half to two-thirds as long as the spikelet, third equaling the 

 spikelet. 



