MANUAL OF THE GRASSES OF THE UNITED STATES 



747 



Florida and southern California but do not flower there. 

 Greek kumbe, boat, 

 and pogon, beard, allud- 

 ing to the boat-shaped 

 spathes. 



Name from 



Vetiveria zizanioides 



(L.) Nash. Vetiver. 

 (Fig. 1666.) Robust 

 densely tufted peren- 

 nial with simple culms 

 and large erect panicles, 

 the slender whorled 

 branches ascending, 

 naked at the base, the 

 awnless spikelets muri- 

 cate. Also called khus- 

 khus and khas-khas. 

 % — Native of the 

 Old World, frequently 

 cultivated in tropical 

 America for hedges and 

 for the aromatic roots, 

 these being used for 

 making screens and 

 mats which are fragrant 

 when wet. Vetiver oil 

 is much used in perfum- 

 ery. Escaped from cul- 

 tivation in Louisiana. 

 Name from vettiver, the 

 native Tamil name. 



146. HYPARRHENIA 

 Anderss. 



Spikelets in pairs as 

 i n Andropogon, but 

 spikelets of the lower 

 pairs alike, sterile, 

 and awnless ; fertile 

 spikelets 1 to few in 

 each raceme, terete or 

 flattened on the back 

 (keeled toward the sum- 

 mit in Hyparrhenia 

 rufa), the base usually 

 elongate into a sharp 

 callus, the fertile lemma 

 with a strong genicu- 

 late awn; sterile spike- 

 lets awnless ; racemes 

 in pairs, on slender peduncles, and subtended by a spathe. 



Figure 1666.— Vetiveria zizanioides, X Vi. (Hitchcock 9435, Jamaica.) 



Tall per- 



