268 MONOCOTYLODENOUS. 



10 P Glaucum. Stem erect, glabrous, slightly compressed. Leaves linear- 

 lanceolate, acute, upper surface scabrous ; spike cylindrical. Glumes with 

 an accessory one, acute, 3-nerved. Palece 2, the exterior one, obscurely 5- 

 nerved. Awns 8-10, in 2 fascicles. 



^ July — Aug Roadsides. 2 ft. 



There are two or three varieties of this plant, varying in the direction of 

 the stem, and in the number of the flowers in the spikelets, and in being pu- 

 bescent. 



11 P Italicum. SiJem erect, slightiv compressed, tomentose. Leaves very 

 long, channeled, scabrous, the sheath with the throat and margins ciliate ; 

 spikes compressed, with the spikelets many flowered. Involucre longer than 

 the flowers. Glumes 2-flovvered, only one palea to the sterile floret. 



Q\. August— Sept. Wet soils. 2-10 ft. 



12 P Geniculatum. (S^e/wassurgent, geniculate, branching, large. Leaves 

 long, hairy, and scabrous on the upper surface, glabrous beneath. Flowers 

 in large panicles, diffuse. Glumes 1 flowered. 



%. August— Oct. Wet soils. 3-6 ft. 



13 P Anceps. Ste?n compressed, branching, geniculate. Leaves hairy. 

 Sheaths hairy, longer than the joints. Panicle expanding, turning to one 

 side. Glumes 2-3-flowered, perfect and sterile. Faleoe shorter than the calyx. 



% August — Nov. Wet soils, common. 2-4 ft. 



14 P HiANS. Stem slender, decumbent, glabrous. Leaves linear, ciliate, 

 near the base. Sheafhs short, contracted and pubescent at the throat. Flow- 

 ers in racemose pancies. Glumes ovate, acute, 2 flowered. Valves of the 

 sterile floret long, of the fertile ovate cartilaginous. 



<v) August — Oct. Pine barrens, common. 10-15 in. 



15 P Latifolium. Stem procumbent, pubescent. Leaves ovate-lanceo- 

 late, hairy at the throat. Flowers solitary, scattered. Glumes 2-flowered, 

 perfect and sterile, pubescent. Palcce of the perfect flowers larger than tho.se 

 of the sterile ones. 



% Through the Summer. Dry shady soils, common. 12-15 in. 



14 P ScoPARiUM. Stem erect, villous. Leaves glabrous on the upper sur- 

 face, 3-6 inches long, 1-2 wide, pubescent beneath. Flowers few, lai-ge. 

 Glumes 2-flowered, pubescent, with an accessory valve. Palece of the perfect 

 floret larger than those of the sterile one- 



% April— May. Shady places. 2-3 ft. 



17 P Pauciflorum. Stem erect, geniculate, branching at the joints. 

 Leaves narrow-lanceolate, acute, ciliate at the base. Sheaths hairy. Flow- 

 ers large, solitary, few. Glumes 1-flowered, with an accessory valve. 



%. May- Damp soils. 12-18 in. 



18 P ViRGATUM. Stem erect, glabrous. Leaves somewhat serrulate, long. 

 Sheaths shorter than the joints. Panicle large, with the branches often verti- 

 cillate. Glumes 2-flowered, perfect and sterile with an accessory valve. 



% August— Sept. Sea coast. 4-6 ft. 



19 P Amarum. Stem erect, stout, glabrous. Leaves flat, thick, throat 

 of the sheath contracted, purple. Panicle large. Flowers large. Peduncles 

 glabrous- Glumes 2-flowered tinged with purple Palece nearly equal in both 

 flowers. 



%. October. Sand hills on the sea coast. 2-3 ft. 



20 P ScABRiuscuLUM. Stem erect, large, somewhat pubescent, scabrous. 

 Leaves lineai-lanceoiate, pubescent beneath, serrulate. Sheaths pubescent, 

 hairy at the throat. Pfl'7«"cZe.<f large, expanding. PedMnc/es glabrous. Glumes 

 2-ftowered, perfect and- sterile. 



% Sept.— Oct. Low country of Ga. 2-3 ft. 



21 P Nervosum. Stem erect, glabrous. Leaves lanceolate, slightly cor- 

 date, ciliate at the base, distinctly nerved. Panicle diffuse. Peduncles pu- 

 bescent. Glume 2-flowered. 



%. May— July. Dry soils. 2-3 ft. 



