616 FLORA OF TEXAS. 



P. Texanum, Buckley. Culms erect or subdecumbent, 



smooth ; sheaths shorter than the internodes, subpubescent 

 and hairy at their mouths ; upper portion of the internodes 

 and joints pubescent; leaves 6-10 inches long and 8-10 

 lines broad, long acuminate, under surface subpubescent; 

 2)anicle compressed,. 5-8 lines long and 5-7 lines broad; 

 rays alternate, erect; lower glume ovate-acute, ^ shorter 

 than the floret, 5-nerved ; upj^er one 7-nerved, acute, hya- 

 line, between the nerves subpubescent, longer than and 

 covering the floret. Several stems grow from the same 

 root. Stems sparingly branched; seeds numerous and 

 aggregated. Austin, Texas, where it is cut for hay, of 

 which horses and cattle are very fond. It grows thick in. 

 cultivated fields, and yields from 1-2 tons of hay per acre. 

 It is a very valuable grass for the South. 



CENCHRUS, L. CocKSPUR. 



Prostrate or creeping grasses, with the spikelets of Pani- 

 cum proper, but inclosed, 1-several together, in spiny or 

 bristly, at length indurated and deciduous involucres, the 

 latter burr-like, and arranged in a terminal spike ; sta- 

 mens 3 ; styles united below. 



C. ECHINATUS, L. Spikes cylindrical, composed of 20 

 or more globular involucres (3-1:' long) ; involucre downy, 

 spiny above, and with a row of rigid barbed bristles above 

 the base, 3-5-flowered ; culms ascending. Fields and 

 waste grounds. July-September. Culms l''-2° long ; m- 

 voliicre purplish. Annual. 



C. TRiBULOiDES, L. Livolucres whitish, 10-15 in a spike, 

 wedge-shaped at the base, armed above with stout com- 

 pressed broadly subulate erect or spreading spines ; bristles 

 none ; spikelets mostly by pairs. Sands along the coast. 

 July-October. Culms prostrate, l°-2° long; leaves linear; 

 spikes l'-2' long. Annual. 



