18 



leaves and sheaths. Mnch of the material in the herbarium hitherto referred 

 to this species belongs to />. racemosus commutatufi and B. secalinus, and the western 

 material especially is in great part B. hordeaceus glahrescens, which is distinguished 

 by its denser panicle with shorter branches. 

 2a. BROMUS RACEMOSUS COMMUTATUS (Schrad.) Hook. f. Stud. Fl. 

 Brit. Isl. 451. 1870. Bromu-^ commutniths Schrad. Fl. Germ. 353. 1806. 

 Serrafalcm eommutatus Bab. Man. Brit. Bot. 374. 1843. 

 An annual or biennial, 3-7 dm. high, typically with a rather small panicle, but fre- 

 quently, under favorable conditions of growth, with a panicle as large as that of 



B. aecalinus, but more droop- 

 ing. It differs from the spe- 

 cies in its rather larger spike- 

 lets and panicle, also rather 

 broader flowering glumes 

 with frequently a faint indi- 

 cation of an angle on the 

 margin just above the mid- 

 dle. The spikelets 2-2.5 cm. 

 long, 6-7 mm. wide, inter- 

 mediate in size between B. 

 racemosus and B. squarroftus; 

 from the latter it differs in its 

 straight awn also. From B. 

 arvensis it is separated bj' its 

 smaller drooping panicle and 

 larger spikelets. 

 Tliis plant seems to be quite gen- 

 erally intrt)duced through- 

 out the country, and espe- 

 cially in the East. 

 Specimens examined. — MassacJiu- 

 setts: Essex Co. (Oakes). 

 Connectinil : Fairfield (E. H. 

 Fames). Xe/r VorJ:: Ithaca 

 (F. V. Coville). Penasyl- 

 vania : Easton (T. C. Porter) . 

 Maryland: Marshall Hall (C. 

 L. Pollard 303). Olrin: 

 Oberlin (A. E. Kicksecker); 

 Painesville (W. C. Werner). 

 Tennessee : K n o x v i 1 1 e ( A . 

 Ruth). Michigan: Agricul- 

 tural College ( C. F. Wheeler ) . 

 Jowu: (L. H. Pammel 909). 

 Missouri: Sheffield (B. F. 

 Bush 599 ) . Wa.sh hu/ton : Pull- 

 .\. & E. G. Heller 3983). 



Fig. 2. — Bromtis mnmosuf: a, lower portion of a .spikelet; 

 /), flowering glume, dorsal view. 



man (A. I). E. Elmer 886); near Montesano (A 

 Oregon: Otis Creek (J. B. Lei berg 2338). 



3. BROMUS HORDEACEUS L. S]). PI. 1: 77. 1753. Bromus mollis L. Sp. PI. 

 ed. 2. 1:112. 1762. ,SWT«/fl7cu.s ?/io///*' Pari. Fl. Ital. 1: .39.5. 1848. (Fig. 3.) 



An erect or ascending annual or biennial irith n rallicr dense, erect panicle. Culms 

 about 2-8 dm. high, usually somewhat pubescent at the nodes. .Sheallis relrorsel;/ 

 sofijiilose-piibescent ; ligule 1.5-2 mm. long, laciniate; blades linear, varying from 



