PANici': 1. 



51 



2. Di<ritaria, Rich. 



Annuals or perennials. The spikelets are lanceolate, 2- to 

 3-nate, in digitate or racemose spikes, jointed on the pedicels 

 but not thickened at the base, I-flowered. There are usually, 

 four dissimilar glumes in the spikelet. The first glume is hyaline 

 very minute, sometimes absent in the same species. The second 

 glume is membranous, I- to 5-nerved or nerveless. The third glume 

 is membranous, almost equal to the fourth, usually 7- to Q-nerved, 

 the nerves being straight, close, parallel and prominent, with a 

 minute palea or without a palea. The fourth glume is chartaceous 

 or sub-chartaceous, usually 3-nerved and paleate ; palea is equal to 

 and similar to the fourth glume, 2-nerved. Lodicules are two, 

 small, broadly cuneate. Stamens are three. Styles are distinct 

 with plumose stigmas exserted laterally near the apex of the 

 spikelet. Grain is enclosed in the fourth glume and its palea. 



KEY TO THE SPECIES. 



Spikelets 1/10 inch or more. 

 Spikes usually few, 

 bearded ... 



spikelets 



Spikelets not bearded 



Spikes usually many ; spikelets 



spreading 

 Spikelets less than 1/10 inch. 



Spikes narrowly winged; spikelets 



subsilky with slender (not cla- 



vellate) hairs 



1. D. sanguinalis. Var. 



ciliaris. 



2. Do. Var. extensum. 



3. Do. Var. Griffith ii 



4. D. longiflora. 



