228 



SOUTH INDIAN GRASSES 



Aristida mutabilis, Trin. & Rup. 



This is a small tufted annual grass with simple or branched 

 slender stems spreading at the base, and sometimes geniculately 

 ascending and rooting at the lower nodes, 6 to 12 inches long. 

 The nodes have dark purple rings when dry. 



The leaf-sheath is glabrous, with membranous margins and long 

 hairs at the mouth. The ligule is a row of short dense hairs. 



The leaf-blade is slender, convolute, rigid, curved, and the tip 

 ending in a sharp point, I to 3 inches long. 



The inflorescence is a narrow panicle, cyiindric, with short 

 crowded branches, some of them remote lower down, peduncle is 

 smooth, and rachis smooth or scaberulous ; branches and pedicels 

 are scaberulous. 



The spikelets are shortly pedicellate, pale-green about V\ inch 

 long exclusive of the awn. There are three glumes. The first 



Fig. 176. —Aristida mutabilis. 

 1. A spikelet ; 2, 3 and 4. the first, second and the third glume, respectively ; 5. grain. 



glume is membranous, oblong-lanceolate, shortly awned, I-nerved, 

 keeled and scaberulous on the keel and the sides. The second 

 glume is narrower and longer than the first, shortly awned I- 

 nerved, 2-toothed, obscurely scaberulous and encircling the third 

 glume. The third glume is narrow, convolute, scaberulous, 3-nerved 

 awned with a shortly bearded callus, the awn is three branched 

 articulate to the short column at the base about 24 inch long 

 with the middle branch slightly longer than the other two; palea 

 is minute. Lodicules are two and narrow. The grain is narrow 

 as long as the glume and grooved. 



This resembles in general habit and appearance Aristida 

 Adscenscionis, but it is not so widely distributed. So far this has 

 been noticed only in Tinnevelly and Nellore districts. 



Distribution. — Southern India, the Punjab and Rajputana, also 

 in Arabia and tropical Africa. 



