GRAPTOPHYLLUM 



GRASS 



1393 



— About 5 species, oriental. No two Ivs. are marked 

 exactly alike, but the yellow color is near the midrib 

 rather than at the margins. The genus is close to Thyrs- 

 acanthus, but in ThjTsacanthus the fls. are not so 

 distinctly 2-hpped. For cult., see Justicia. 



hortense, Nees [G. pictum, Griff. G. piduratum, 

 Hort. Justicia pida, Linn.). Caricature Plant. 

 Height finally 6-8 ft.: Ivs. elliptic, acuminate, irregu- 

 Jarly marked with yellow along the midrib: fls. crim- 

 son, in axillary whorls; corolla pubescent. Habitat (?). 

 B.R. 1227. Lowe 4.5. B.M. 1870 shows a variety with 

 reddish brown coloring. — A yellowish -fid. form has 

 been offered under the name G. piduratum, but it does 

 not seem to differ otherwise. fj_ TATLOR.f 



GRASS {Gramineae). Annual or perennial, mostly 

 herbaceous plants with usually hollow sts. (culms) 

 closed at the joints (nodes), and 2-ranked Ivs. Culms 

 woody in the bamboos and in a few other groups such 

 as the genus Lasiacis, sometimes sohd as in maize: 

 Ivs. consisting of two parts, the sheath and the blade, 

 the sheaths enveloping the culm above each node, the 

 margins overlapping or occasionally grown together as 

 in Bromus and MeUca, the blades parallel-veined, 

 usually Unear or elongated (in some tropical grasses short 

 and broad), on the inside bearing at the junction with 

 the sheath a membranous or hyaline appendage or rim 

 called the Ugule; in some tropical grasses, especially 

 bamboos, a petiole inserted between the sheath and 

 blade: infl. paniculate or contracted into a raceme or 

 spike, or more rarely into a head, the branches usually 

 bractless; fls. usually perfect, sometimes monoecious as 

 in maize, or dioecious as in salt-grass (Distichlis), small, 



without a distinct peri- 

 anth, arranged in spike- 

 lets consisting of a short- 

 ened axis (rachiUa) and 2 

 to many 2-ranked bracts, 

 the lowest pair (the 

 glumes) empty, one or 

 both of these sometimes 

 absent; each succeeding 

 bract (lemma) including a 

 single fl. and, with its back 

 to the rachilla, a 2-nerved 

 bract or prophyllum 

 (palea), the fl. with its 

 lemma and palea being 

 termed the floret; stamens 

 usually 3, with deUcate 

 filaments and 2 - celled 

 versatile anthers; pistil 1, 

 with a 1-celled, 1-ovuled 

 ovary, usually 2 styles 

 and plumose stigmas: fr. 

 a caryopsis with starchy 

 endosperm, and a small 

 embryo at the base on 

 one side; grain (caryopsis) 

 inclosed at maturity in 

 the lemma and palea (or 

 sometimes exceeding these 

 as in maize and pearl 

 millet), adherent to the 

 palea as in the oat, or free 

 as in wheat. Figs. 1745- 

 1748 show the structure 

 of various grass florets. 



The lemmas are some- 

 times empty and are then 

 termed sterile lemmas to 

 distinguish them from the 



1^..* 171 » . , s glumes. The spikelets 



1746. Floret of a grass (rye). ° i_ ■ i j- „,, 



cc, lemma and palea: a. stig- may be mclosed in a spiny 



mas: bbb, stamens. (Much involucre or bur as in the 



enlarged.) sand-bur, or in an in- 



89 



durated shell as in Job's tears (Coix), or the entire 

 spike in numerous husks as in maize. 



The perennial species of grasses may produce creep- 

 ing underground stems (rhizomes) by which they 

 propagate. Kentucky blue-grass and 

 awnless brome-grass are examples of 

 this class. Such grasses usually form 

 ■ a sod. Those, such as orchard-grass, 

 in which no rhizomes are produced 

 usually grow in bunches or tus- 

 socks and are known as bunch- 

 grasses. 



The true grasses {Graminex) may 

 be distinguished from other grass- 

 hke plants such as sedges {Cyperacex) 

 and rushes (Juncacese) by the two- 

 ranked leaves and the cyhndrical or 

 flattened stem. Sedges have three- 



1747. Spike of a grass 

 (rye), containing many 

 spikelets. 



1748. Staminate spikelet of a grass 

 (maize), showing two flowers, one of 

 which (with three stamens) is ex- 

 panded. I, I, glumes; 2, 2, palea. 

 (Enlarged.) 



ranked leaves and usually a triangular stem. There 

 are also important differences in the floral structure. 



A. S. Hitchcock. 



Uses 0} grasses. 



Among the species most commonly known are timo- 

 thy, red top, June -grass, orchard-grass, meadow fox- 

 tail, the fescues, oat-grass, sweet vernal, quack-grass, 

 Bermuda-grass, sugar-cane, chess, and the cereals, such 

 as wheat, barley, rye, oats, rice, sorghum, Indian 

 corn. In number of species the grass family occupies 

 the fifth place with 3,500, while the composita;, legumes, 

 orchids and madderworts are larger. In number of 

 individuals, the grasses excel any other family. Seed 

 plants are arranged in 200 to 220 famiUes, and of all 

 these the true grasses are of greatest importance; in 

 fact, they are of more value as food for man and donies- 

 tic animals than all other kinds of vegetation combined. 

 None of these famihes is more widely distributed over 

 the earth's surface, or is found in greater extremes of 

 climate or diversity of soil. 



The species are very numerous in tropical regions, 

 where the plants are usually scattered, while in a moist, 

 temperate cUmate, although the species are less numer- 

 ous, the number of plants is enormous, often clothing 

 vast areas. Where soil is thin or moisture insufficient, 

 the grasses grow in bunches more or less isolated. 

 Plants of one section of the family, Panicacea;, preilomi- 

 nate in the tropics and warm temperate regions, while 

 plants of the other section, Poaceaj, predominate in 

 temperate and cold regions. 



Overstocking dry grazing districts checks the better 

 grasses, destroying" many of them, anfl encourages the 

 bitter weeds which multiply and occupy the land. 



