PLANTS OF SOUTHERN NEW JERSEY. 179 



jj. Spjkelets ovate, not flattened. 



Syntherisma, p. i88 

 a. Flowers awned, scattered, or occupying 

 only the end of the rachis; rachis not 

 flattened. Gymnopogon, p. 234 



hhh. Arranged on short spikes, all closely ap- 

 pressed to the main stem and scarcely over- 

 lapping. 



i. Awned. Muhlenbergia, p. 211 



ii. Not awned. 



j. Spikelets conspicuously flattened. 



Homalocenchrus , p. 215 

 ij. Spikelets ovate, not flattened. 



Panicum, p. 189 

 hhhh. Arranged in a slender appressed panicle. 

 i. Panicle very slender, but few short 

 branches, all closely appressed, flowers 

 long awned; awns 18-24 mm. long. 



Brachyelytrum, p. 221 

 ii. Panicle of appressed branches, flowers 

 not long awned; awns, if present, less 

 than 10 mm. 

 j. Culms simple. 



k. Leaves involute. 



Panicum amarum, p. 196 

 kk. Leaves not involute, panicle 

 dense and feathery. 

 ;. A tuft of hairs at the base 

 of the flowers within the 

 glumes. 

 Calamagrostis canadensis, p. 227 

 II. No tuft of hairs. 



m. Inflorescence whitish or 

 reddish, erect. 



A'grostis, p. 224 

 mm. Inflorescence green 

 drooping. Cinna, p. 224 

 ;■/. Culms much branched with nu- 

 merous lateral panicles. 



Muhlenbergia, p. 211 

 gg. Spikelets two to many flowered. 



h. Spikes digitate or branching off in a fan-like 

 arrangement from the common stalk. Spike- 

 lets sessile or nearly so. 

 i. Spikelets in two definite rows, contigu- 

 ous. [Bleusine indica]* 

 ii. Spikelets not in two definite rows, scat- 

 tered. Diplachne, p. 237 



* Crab grass. A common weed in lawns and about gardens, 



