PANICE^. 157 



Georgia to Florida. 



11. C. imberbis (Poir) Kuntze, Rev. Gen. PI. 767 (1891), 

 Panicum imberbc Poir, Lam. Encyl. Suppl. 4 : 272 (1816). >S'e- 

 taria imberbis, R. & S. Syst. 2:891 (1817). 



Culms erect, slender, branching sparingly, 30-50 cm. high. 

 Sheaths often longer than the internodes; ligule very short; blades 

 flat, smooth or scabrid or soon involute, 6-18 cm. long, 3 mm. 

 wide. Spike simple, cylindrical, green, 4-5 cm. long, 4-5 mm. 

 diam., awnlike branches about 5, with the asperities directed up- 

 wards, branches 4-6 mm. long. Spikelets flat on one side, ovoid, 

 pointed, about 2 mm. long, first glume broad, half as long as the 

 spikelet, 5-nerved, second longer and wider, 5-7-nerved; fertile 

 floret gibbous on one side, marked with transverse wrinkles. 



Texas, Kealley. 



Mississippi and Texas. 



12. C. viRiDis (L.) Porter, Bull. Torr. Club, 20:196 (1893). 

 Pigeon-grass. Bottle-grass, Green Foxtail. Panicum 

 viride L. Sp. PI. Ed. 2 : 83 (1762). Setaria viridis Beauv. Agrost. 

 51 (1812). 



Culms erect, branching below, 30-60 cm. high. Ligule and 

 margins of sheaths ciliate; blades flat, scabrous, not twisted while 

 growing, acuminate, tapering toward the base, on large plants 

 15 cm. long, 10 mm. wide. Spikelike panicle erect, green, nearly 

 cylindrical, 3-8 cm. long. The lower spikelets in small clusters, 

 the upper fewer or single, the bristles, 1-5 for each spikelet, often 

 10 mm. long, the asperities directed upwards. Spikelets oval, 2 

 mm. long, flrst glume one-half as long, 1-nerved, second and tliird 

 glumes equal, 5-7-nerved; fertile floret oval, the surface containing 

 minute vertical lines, seen only under a lens. 



Very common in fields which are in cultivation, resembling con- 

 siderably small forms of C. Italica. It starts earlier in the spring 

 and flowers much earlier than C. glauca in the Northern States. 



Michigan, M. A. C. Beal 25, 26, Farwell, Clark 752; Montana, 

 Anderson 17. 



13. C. caudata (Lam.). Panicum can datum Lam. III. 1:171 

 (1791). Setaria caudata R. & S. Syst. 2: 495 (1817). 



