MACLOSKIE : REVISION OF FLORA PATAGONICA. 29 



smooth; glumes (I and II) as long as the spikelet, broad-ovate, acute, 

 smooth, 3-nerved; floral glumes (III and IV) nearly as long as the 

 spikelet, broad ovate, scabrous, y-nerved, enclosing a narrow, 2-nerved 

 palea and 3-androus flower ; fertile glumes (V) shorter than the spikelet, 

 oval, obtuse, smooth, almost nerveless ; palea of the same length, broad 

 oblong, 2-nerved. 



Very near to H. pauciflora R. Br. The last mentioned differs, however, 

 from the present species by its smooth culm, by the short glumes (the 

 first and second are a little shorter than the third and fourth, in H. pusilla, 

 on the other side, being longer) by the floral glumes (the third and fourth 

 being a little hairy at their margin but not at the apex), the fourth one having, 

 besides, a short awn below the emarginate apex. D. 



ARISTIDA L. 



A. DIFFUSA Trin. et Rupr. and A. SETIFOLIA H.B.K. Macl., p. 168. 

 Not found in Patagonia ; both species should be deleted. 



STIPA L. 



S. CHUBUTENSIS Speg. 



Awn several times longer than floret, villous in lower part, glumes as 

 long as the pappus and lower joint of the awn. Leaves convolute, 

 glabrous, rigid. Culms much longer than leaves ; nodes naked, black 

 pubescent ; panicle closely infolded in the upper spathe-like sheaths. 



E. Patagonia, Puerto San Antonio in drift-sand fields ; Central Pata- 

 gonia, the Chubut Territory by Teka-choique. 



Add Macl., p. 171 : 



S. HUMILIS Cav. 



Cespitose, 10 16 cm., glabrous. Upper sheath ventricose, about a short, 

 dense panicle. Glume acute, thrice as long as flower. Awn near the 

 base, straight, with white hairs to the joint, thence pinnated. 



S. Patagonia (not in Magellan), certainly also in Central Patagonia, 

 from the east coast to the eastern slopes of the Cordillera, very often 

 abundant. 



A low grass growing in small, dense tufts, very common, especially in 

 the western part of its range, where, alone or associated with a few other, 

 sparingly occurring plants, it occupies the vast drift-sand fields at the 

 middle and eastern parts of the great lakes. 



