30 GEAMINEAE 



2. S. purpurea (Walt.) Kuntze. SAND-GRASS. A tufted animal, 

 about 1 high : leaves short, sparingly ciliate : panicle -%' long. In 

 sand in the Missouri River bottom at Courtney. Common in one 

 locality. Also occurs at Quindaro, Kansas. July-September. 



38. DIPLACHNE Beauv. 



Spikelets several-flowered, sessile on the rachis, forming slender 



spikes. Two lower glumes empty, keeled, acute, unequal. Flowering 



glumes longer, 1-3-nerved, 2-toothed and mucronate between the teeth. 



Spikelets 2 // -4 // long. 1. D. fascicularis. 



Spikelets 5"-6" long. 2. D, acuminata. 



1. D. fascicularis (Lam.) Beauv. A decumbent or ascending annual, 

 l-3 high : spikes panicled, partly enclosed in upper sheath : spikelets 

 3 // -5 // long, 5-11-flowered. Often common on muddy shores in low 

 grounds. June-October. 



2. D. acuminata Nash. Resembles the last, but spikelets longer, 

 the flowering scales acuminate, entire (obtuse and two-toothed in D. 

 fascicularis}. Often common on mud-flats, especially at Courtney. 

 June-September. 



39. ERAGROSTIS Beauv. 



Spikelets paniculate, 2-many-flowered, flattened. Two lower glumes 

 empty, short and keeled, 1-nerved. Flowering glumes keeled, 3-nerved, 

 not pilose at base. Palet 2-nerved, persistent on the rachis after the rest 

 of the flower has fallen. 



Culms creeping and rooting. 1. Itypnoides 



Culms ascending or erect. 



Spikelets large and flat, forming a narrow crowded 



panicle. 2. E. major. 



Panicle open, its branches capillary. 

 Culms H high or less. 



Spikelets 5-many-flowered. 3. E. Pttrsltii. 



Spikelets 2-5-flowered. 



Culms much-branched. 4. E. Frankii. 



Culms sparingly branched. 5. E. capillaris. 



Culms 1 J or more high. 



Spikelets yellowish, usually 3-5-flowered. 6. E. irichodes. 



Spikelets purplish, usually 6-10-flowered. 7. E. pectlnacea. 



1. E. hypnoides (Lam.) B.S. P. Annual, forming large patches 

 leaves short, 6 // -18 // long : flowering branches 2 / -5 / high : spikelets 

 dioecious, 10-30-flowered, 2 // -8 // long, clustered. Common along 

 streams, especially along the Missouri River. June-October. 



2. E. major Host. 6 x -2 high : leaves flat, sharp-pointed, 4 / -6 / 

 long : panicle 2 / -6 / long, \\ f -^\' wide : spikelets lance-oblong, 3"-6" 

 long, lj /x wide, usually 8-20-flowered. Common in waste places. 

 July-October. 



3. E. Purshii Schrad. Densely-tufted and much branching, 3 / -18 / 

 high : leaves about 2 / long: panicle from 1 / -10 / long, its branches loose 



