BusJi — North American Species of Triodia. 77 



ing scales about 6 mm. long, obtuse at the scabrous apex, 3- 

 nerved, the lateral nerves vanishing at or below the apex, the 

 mid-nerve usually excurrent as a short tip. Barrens and 

 rocky prairies. Common southwest ward. June to October. 

 Perennial. 



Upper Sonoran area. Missouri and Kansas to Arkansas, 

 Indian Territory, Oklahoma, Texas, Colorado and Arizona. 



Type locality not ascertained. 



Specimens examined. — Missouri: Eagle Rock, Barry County, Bush, 



689, 1896 Texas: Dallas County, Reverchon, 445; same locality. Bush, 



1134, 1900; same locality, Beverchon, 1109, 1900 — San Antonio, Bush, 842, 

 1901.— Kansas: Chautauqua County, Hitchcock, 919. 1896 — Colorado: 

 Canon City, Brandegee, 360, 1874. 



EXPLANATION OF ILLUSTRATIONS. 



Plates X.-XI. 



Plate X. — Triodia congesta, habit, reduced one-half, and spikelet, X 2. 

 Plate XL— Triodia Nealleyi, habit, reduced one-half, and spikelet, X 3. 



Issued June 9, 1902. 



