160 



GRASSES OF IOWA. 



(Cratty) ; 763, Ledyard (Pammel and Cratty) ; Keokuk (Hitchcock) ; 

 766, Montrose (Osborn) ; Greenfield (Stewart) ; Hamilton to Han- 

 cock (Preston); Mason City (Pammel). 



North America. From New England south to Kentucky (Harlan 

 County, Kearney) ; west to Wisconsin (La Crosse, Pammel), Illinois 

 (Eggert; Bluff Lake, Pammel), Kansas, Missouri (St. Louis, Pammel; 

 Plattsburg, Tracy). 



4. SPOROBOLUS CUSPIDATUS. 



Sporobolus cuspidatus. Wood. Bot. and Fl. 385. 1870. 



Sporobolus cuspidatus. Watson and Coulter in Gray. Man. Bot. 646. 

 1890. <6th ed.) Vasey. Contr. U. S. Nat. Herb. 3: 60. 



Sporobolus cuspidatus. Wood. Nash in Britton and Brown. 111. Fl. 1. 

 153. /. 347. 1896. 



Sporobolus brevifolius. Scrib. Mem. Torr. Bot. Club. 5: 39. 



Sporobolus cuspidatus. (Nutt,) Scrib. Beal. Grasses of N. A. 2: 288. 



1896. 



Agrostis brevifolia Nutt. Gen. 1: 44. 1818. (In part.) 

 Vilfacuspidata. Torr. Hooker. Fl. Bor. 2: 238. 1S40. 



DESCRIPTION. 



Prairie Rush Grass. Smooth and 

 glabrous, culms 1 to 2 feet (2-5 dm.) 

 tall, erect, simple or somewhat branched. 

 Sheaths shorter than the internodes; ligule 

 a mere ring,! nne (I mm.) long or less, 

 erose-truncate ; leaves 1 to 4 inches (2-10 

 cm.) long, less than 1 line (2 mm.) wide 

 at the base, erect, involute-setaceous, at 

 least when dry; panicle 1^ to 5 inches (3- 

 10 cm.) in length, slender, its branches \ 

 to 1 inch (-J-2 cm.) long, appressed ; spike- 

 lets 1 1 to 1^ lines long, the outer scales 

 half to three-quarters as long, acuminate or 

 cuspidate, scabrous on the keel ; third scale 

 long-acuminate and cuspidate, sparingly 

 scabrous. In dry soil. August-September. 



DISTRIBUTION. 



Iowa. Mason City (Pammel) ; Wood- 

 bine (Burgess) ; 793, Armstrong (Pammel 

 and Cratty) ; 927, Emmet County (Pam- 

 mel and Cratty) ; Carroll, 1027 Kossuth 

 County, Turin, 656 Des Moines, South 

 Dakota opposite Hawarden, 257 Turin 



Sioux City, 128 Carroll (Pammel) ; 779. Fig. »*• Sporobolus cuspi- 



,, , , T , , , . , ,,. ..,,. , , .. dalus—a, spikelet. (CharlotteM. 



Bartlett (Baldwin) ; Sioux City (Miss King.) 



