10 



X 



(Panicle frequently more lax than represented in figure.) Spike- 

 lets 2-4 cm. long, four to ten-flowered, purplish in color; empty 



glumes unequal, the first 5-7 mm. long and one-nerved, the 

 second 7-9 mm. long and three-nerved, nerves purple; flowery 



glume 9-12 long with a short scabrous awn, seven-nerved (three 

 nerves much more prominent than the others), ciliate pubescent 

 on the margins and prominent nerves below. (Often less acute 

 than illustrated, and sometimes slightly notched at the scarious 

 tip.) Palea shorter than, or sometimes nearly equalHng, its glume, 

 narrow and ciliate on the nerves. 



Brofntis ciliatus^ L. var. Coloradensis, Vasey, in Bot. Wheeler, 

 Montana, No. 418, Scribner, and in various collections from 

 the Rocky Mountain region. No. 518, Tweedy, 1885, from the 

 Yellowstone National Park, is a smaller flower form, with only 

 3-5 florets in each spikelet, and with flowering glumes much 

 more densely pubescent. F. LamsON Scribner. 



Washington, D. C, Dec. 10, 1887, 



EXPLANATION OF PLATE. 



A. Mtihlenbergia Arizonica, i. Plant entire^ much reduced. 

 2. Dorsal view of spikelet. 3. Anterior view of spikelet. 4. 

 Floret. 5. Empty glumes. 6. Dorsal view of flowering glume, 

 flattened. 



B. Sporoholiis mtcrriiptiis^ Vasey. i. Plant entire, much re- 

 duced. 2. A branchlet wath four spikelets. 3. A spikelet 

 4. A floret. 5. Apex of palea. 



C. Deyeiixia Stiksdorfii, I. Spikelet. 2 and 3. Empty 

 glumes. 4 and 5. Dorsal and anterior views of the floret. 6. 

 Apex of flowering glume. 7. Apex of palea. 8. Rudiment. 

 9. Anther. (The details all drawn to the same scale excepting 



fig- 9-) 



D. Bromiis Pumpellianus, I. Plant entire, much reduced. 



2. A spikelet. 3, Anterior view of floret. 4. Dorsal view of 

 same. 5- Dorsal view of flowering glume, flattened. 6. A sta- 

 men. 7. Ovary, styles and lodicules. 



Note. — All these figures drawn from nature and designed for 

 Dr W. J. BeaFs work on the '* Grasses of North America/' 

 Used here by permission. 



