48 HYDRALES 
Fourth scale with a long bent awn, twisted at the base. 
Empty scales hispidulous all over, hairs on rachis internodes 2 
mm, long. 2. A, furcatus. 
Empty scales smooth except on the nerves, hairs on rachis inter- 
nodes 3-4 mm. long. 3. A. chrysocomus. 
Fourth scale awnless or with a short, straight, untwisted awn. _ 
Pedicels and rachis internodes with copious, stiff, marginal hairs. 
. 4. A. hallii. 
Pedicles and rachis internodes with scant, lax, marginal hairs. 
5. A. paucipilus. 
1. Andropogon scoparius Michx. Little Blue-stem. 
Common on the prairies all over the state. Anselmo; Deuel County; 
Dismal River; Grand Rapids; Halsey; Lincoln; North Platte; Repub- 
lican; Valentine. 
2. Andropogon furcatus Muhl. Big Blue-stem. 
Common in prairies throughout the state. Beaver Creek in Holt 
County; Franklin; Gage County; Halsey; Lincoln; Mullen; Thedford; 
Wahoo; Whitman; Valentine. 
3. Andropogon chrysocomus Nash. 
Halsey. 
4. Andropogon Hallii Hack. Big Blue-stem. 
Common on high prairies in the central and western parts of the state. 
Antelope County; Banner County; Box Butte County; Chelsea; Gar- 
den County; Haigler; Lawrence Fork; Long Pine; Plummer Ford; 
Thedford; Valentine. 
5. Andropogon paucipilus Nash. 
Nebraska, according to Britton’s Manual, 
2. Sorghastrum. 71. 
1. Sorghastrum avenaceum (Michx.) Nash, 
Sorghastrum nutans (L.) Nash. 
Common on the prairies. Ayr; Carns; Dismal River; Deuel County; 
Hardy; Halsey; Lincoln; North Platte; Thedford; Valentine. 
Tribe 10. Maydeae. 
1. Tripsacum. 67. 
1. Tripsacum dactyloides L, 
In low wet places in the southeastern part of the state. Nemaha; 
Richardson County; Weeping Water. 
HYDRALES. 
HYDROCHARITACEAE. 
Philotria. (Elodia.) 60, 
1. Philotria canadensis (Michx.) Britton, 
In ponds and streams, rare. Ewing; Neligh. 
IRIDALES, 
Stamens 6. 1. Amaryllidaceae, 
Stamens 3. 2. Iridaceae. 
