38 



POACEAE. 



29. LEPTOCHLOA Beauv. 



Usually tall annual grasses, with fiat leaves and numerous spikes forming 

 a simple panicle. Spikelets usually 2-many-flowered, flattened, alternating in 

 two rows on one side of the rachis. -Scales 4 to many; the 2 lower empty, 

 keeled, shorter than the spikelet; the flowering scales keeled, 3-nerved. Palet 

 2-nerved. Stamens 3. Styles distinct. Stigmas plumose. Grain free, en- 

 closed in the scale and palet. [Greek, in allusion to the slender spikes.] 

 About 12 species, natives of the warmer regions of both hemispheres. Type 

 species: Cynosurus virgatus L. 



1. Leptochloa filiformis (Lam.) 

 Beauv. Northern Leptochloa. (Fig. 

 57.) Culms l°-4° tall, finally branch- 

 ing. Sheaths, at least the lower ones, 

 commonly more or less hirsute; leaves 

 2Y~10' long, 5" or less wide, rough; 

 inflorescence 6'-2° long; spikes gen- 

 erally elongated, ascending, 2'-6' long; 

 spikelets about IV long; scales usually 

 5, the outer empty 2 acute, equal, or 

 the first somewhat shorter than the 

 second, the first scale usually a little 

 shorter than the first flowering scale. 

 [Eleusine mucronata Michx.; Festuca 

 filiformis Lam.] 



Waste or cultivated grounds. Ap- 

 parently uncommon. Introduced. Native 

 of the southeastern United States and 

 tropical America. Flowers in autumn. 



30. LOLIUM L. 



Annual or perennial grasses, with flat leaves and terminal spikes. Spike- 

 lets several-flowered, solitary, sessile and alternate in the notches of the usually 

 continuous rachis, compressed, the edge of the spikelet (backs of the scales) 

 turned toward the rachis. Scales rigid; lower scale empty in the lateral spike- 

 lets, and the 2 lower empty in the terminal; flowering scales rounded on the 

 back, 5-7-nerved; palets 2-keeled. Stamens 3. Styles distinct, very short. 

 Stigmas 2, plumose. Grain adherent to the palet. [Latin name for Darnel.] 

 About 6 species, natives of the Old World. Type species: Lolium perenne L. 



