repens, Beau v. Quack-grass. (Figs. 159, 564.) A perennial with a creeping, several-jointed root stock. Culms may reach four feet in height. Leaves numerous and linear; spikes six to twelve inches long, erect ; spikelets on opposite sides of a jointed and grooved rachis, erect, four- to eight-flowered. Glumes acute or short-awned ; lemmas smooth ; palea acute or slightly rounded. Also called couch-grass, twitch grass and quitch-grass.
31. Hordeum (Latin name for barley). A genus of about sixteen species of grasses in both hemi spheres. Spikelets one - flowered, two to three together at each joint of the articulated rachis, forming a dense terminal spike. Glumes two, nar row or bristle form.
rulgare, Linn. (or H. sativum, Jess.). Barley. (Figs. 287, 565.) A well-known cereal cultivated in all cool climates. There are normally three spikelets in a group at each node, each with its pair of awn like glumes ; each lemma also long-awned. If all three spikelets are developed and form grains, six or four-rowed barley is produced, according as the lateral spikelets on each side form two distinct rows or are coalesced into one. In two-rowed barley the lateral spikelets are staminate and do not form grains. The grain in most varieties adheres to the lemma in threshing, hut in the naked barleys it falls out. Beardless barley is a form in which the awns are short and much distorted. [See Barley. Authorities differ in practice as to use of the two specific names ; either is allowable.] Literature.
The following is a list of the more important recent works treating wholly or in part of North American grasses. In addition, there are numerous local floras, monographs and technical articles in botanical journals that are not readily accessible to the general reader. Manuals and general works : Beal, Grasses of North America, Vol. II, 1896 ;
Britton, Manual of the Flora of the Northern States and Canada (1901), Second edition, 1905 ; Britton and Brown, An Illustrated Flora of the Northern United States, Canada and the British Possessions, Vol. I, 1896 :Chapman, Flora of the Southern Uni ted States, Third edition, 1897; Coulter, Manual of the Botany of the Rocky Mountain Region, 1885; Gray, Manual of the Botany of the Northern United States, Sixth edition, 1890; Hackel, The True Grasses, translated from the German by Scribner and Southworth, 1890; Small, Flora of the Southeastern United States, 1903; Watson, Geological Survey of California, Botany, Vol. II, 1880 (the grasses are by Thur ber); Monographs and special papers, United States Government pub lications: Hitchcock, North American Species of Agrostis, Bureau of Plant Industry, Bulletin No. 68, 1905 ; Hitch cock, North American Species of Leptochloa, Bureau of Plant Indus try, Bulletin No. 33, 1903 ; Merrill, The Native Species of Chmtochloa, Division of Agrostology, Bulletin No. 21, 1900; Merrill, The North American Species of Spartina, Bureau of Plant Industry, Bulletin No. 9, 1902; Piper, North American Species of Festuca, Contributions from National Herbarium 10, No.
1, 1906; Scribner, American Grasses, I, Division of Agrostology, Bulletin No. 7, 1900 ; II, Division of Agrostology, Bulletin No. 17, 1901 ; III, Division of Agrostology, Bulletin No. 20, 1900; Shear, A Revision of the North American Species of Bromus Occurring North of Mexico,Divisionof Agrostology, Bulletin No. 23, 1900; Vasey, Illustrations of North The figures for hemp in the Twelfth Census (1900) are as follows : American Grasses : Vol. I, Grasses of the Southwest, 1891; Vol. II, Grasses of the Pacific Slope, 1893, Division of Botany, Bulletin Nos. 12 and 13.