GRASSES OF IOWA. 337 



spikelets about 7 mm. Long, on a stipe 1 mm. Long; awn 1.2 to 2 cm. 

 Long. Palea as long as their florets, scabrous on the keels. 



Type collected at Dakota City, Iowa, by L. H. Pammel, No. 3824, 

 August 8, 1896 prairies along the line of the C. & N. W. R. R. 



In the genus Hordeum the spikelets are one-flowered, with a rudi- 

 mentary second flower usually present. H. Pammeli is unique in hav- 

 ing the central spikelet normally two-flowered, with a rudimentary third 

 flower but is still referable to Hordeuml rather than to Elymus. It re- 

 sembles in general appearance H. caespitosum or a very large form of 

 H. nodosum. It is readily distinguished from all other species by the 

 short-stalked or nearly sessile, lateral spikelets, containing a fertile flower. 

 These characteristics show it to be closely related to the common culti- 

 vated barley. See figure 237, on page 336. 



DISTRIBUTION. 



Iowa. Dakota City (Pammel). 



North America. Central Illinois to northwestern Wyoming, in 

 moist situations, sometimes shaded. Apparently rare, and of local distri- 

 bution, though reported as common in the Wyoming locality. Latter 

 part of June to middle of August. 



There are three other collections of this species. Illinois: Wady 

 Petra, NW{, Sec. 31, Valley Township, Stark County, moist bank of 

 ditch V. H. Chase, 45, June 25, 1897, sub nomen Elymus striatus Willd- 

 This was examined in the herbaria of Mrs. Agnes Chase, Washington, 

 D. C, Prof. S. M. Tracy, Biloxi, Miss., and the Field Columbian Mu- 

 seum, Chicago. South Dakota: Brookings, E. N. Wilcox, 68, July 

 8, 1896. Wyoming: Hulett, moist, shady meadow, common, David 

 Griffiths 930, July 17, 1898. The last two specimens are in the her- 

 barium of the office of the Agrostologist, U. S. Department of Agricul- 

 ture. 



6. HORDEUM PUSILLUM. 



Hordeum pusillum Nutt. Gen. 1:87. 1818. Scribner. Grasses of Term. 

 Bull. Univ. Tenn. Agrl. Exp. Sta. 7: 125. /. 181. 1894. Nash in Britton 

 and- Brown. 111. PI. 1: 229. /. 530. 1896. Bull. U. S. Dept. Agrl. Div. 

 Agros. 17: 314. /. 610. 1899. 



Hordeum pratense Huds. Watson and Coulter. Gray. Man. Bot. 672. 

 (6 ed ) Beal. Grasses of N. A. 2: 645. /. 123. 1896. 



22 



