168 



THE TRUE GRASSES. 



valuable forage-grass for such places. The related B. 

 inermis Leyss., with awnless spikelets and creeping 

 rhizomes, is an important pasture-grass for dry climates. 

 The rhizome of Br. catharti- 

 cus Vahl. of Chili is valued 

 there as a purgative. 



Sub-genus II. Stenobro- 

 mus. Low annuals with 

 narrow spikelets becoming 

 broader above. Empty 

 glumes as in Sub-genus I. 

 Flowering glumes keeled, 

 long-awned; palea with a stiff 

 fringe. Weeds. B. Tectorum 

 and B. sterilis L. in all 

 Europe, and introduced in 

 America. Anisantha C. Koch 

 also belongs here. 



Sub-genus III. Zeobromus 

 (Serrafalcus Parl.). Annuals, 

 with ovate or lanceolate 

 spikelets, narrower above ; 

 first empty glume 3-5- 

 nerved, second 5-7-nerved ; 

 (After Nees, flowering glumes 7-9-nerved, 

 not keeled ; awn often spread- 

 ing, rarely wanting ; palea with a stiff fringe of hairs. 

 B. secalinus L. (" Chess"), panicles drooping after flower- 

 ing, leaves smooth ; a weed among crops, in wet years, 

 sometimes very abundant in rye. If the fruit is not 

 separated by a chess-sieve the rye is worthless, for the 

 flour prepared from it will be dark-colored, remain moist, 

 and is narcotic. Br. arvensis L., with similar panicles 

 but hairy leaves, is less dangerous. B. mollis, with the 

 branches of the panicle upright and hairy spikelets, 

 growing in sandy places, furnishes a transient green fod- 

 der on light soils. Triniusa Steud. is a. species usually 

 having three awns. 



Sub-genus IV. Libertia Lejeune (as a genus, MicJie- 

 laria Dum.). Like Zeobromus, but the flowering glume 



FIG. 89. Bromus mollis L 



Gen. Germ., I. 75.) 



