GKAMINKiB. (GRASS FAMILY.) 



873 



leaves; culms branching at base, ^vith scattered 

 longer leaves. Spikes 4-7, .0'^ to .05 long,' green or purplish — All 

 the year — Waste places, especially in sandy soil; everywhere. A 

 most troublesome weed. 



48. TETRAPOGO:^, Dcsf. TEXuAroGON. 

 Spikelets on the outer face of a flattened rachis, 2-ranked, 3-4 



Fig. 307. 



Spike of Tetrapogon 

 villosum. 



alternate, sessile, laterally compressed, '^ 

 cept the uppermost which is tabescent, 



llowered, the lower two fowerets perfect, the others 

 tabescent, consisting of one pale. Glumes 2, persist- 

 ent, membranous, keeled, the lower acuminate, the 

 upper rounded at tip, aristate-mucronate. Lower 

 pale keeled, 3-nerved, obtuse or retuse, loug-awned 

 just below tip ; upper pale retuse, 2-keeled — Peren- 

 nials ; spikelets in 2, erect spikes, adnate by their 

 inner face, appearing to form one, 4-ranked spike. 



T. i^illosuiu, Desf. 21 .2 to .3, tufted; root- 

 stock thickish, with a dense rosette of leaves ; culms 

 erect, sparingly leafy. Leaves glabrous, linear, 

 channeled, the radical somewhat 2-ranked, crowded. 

 Spikes .04 to .06 long, .015 thick (including crowd- 

 ed awns) ; lower pale obovate, obtuse, concave, 

 silky -hairy at back, obtuse or retuse at tip, with an 

 awn twice to four times as long — Spring — Valleys 

 about Dead Sea, and southward to Sinai and 

 Egypt. 



49. BACTlXOCTENIfJM, Willd. Egyptian Grass. 



Spikelets arranged along the outer aspect of the flattened rachis, 



30 -flowered, the flowerets, ex- 

 perfect. Glumes nearly ctpial, 

 keeled, membranous, shorter than flowerets, the upper mucroii:ite- 

 aristate at or a little below tip; upper pale 2-keeled. Annuals; spikes 

 digitate. 



©. iEgyptiacuni, L. Egyptian Grass. Rijl-d-Uarhdych. 

 Nct'hn-es-Salib. A to .6; culms prostrate below, geniculate, rooting at 

 joints, branching. Spikes 3-5, .05 long, .005 broad, mucronate by ex- 

 currence of rachis; loAver glume oblong, acute to acuminate, upper 

 ovate, larger, rounded at lip, retuse, with an awn as long as itself in 

 the notch; lower pale mucronate-aristate, the lateral nerves obsolete — 

 Spring — Sidon (Gaill. in Fl. Or.). 



50. PAPPOPHORUM, Schreb. 

 PAPrornoiiuM. 



Spikelets laterally Compressed, 2-3-flowered, 

 the lowest floweret perfect, the upper staminate 

 or neuter. Glumes lanceolate, many-nerved, 

 muticous, longer than flowerets. Lower pale 

 somewhat leathery, concave, 0-nervcd, the nerves 

 excurrent in straight, subulate awns. Upper pale 

 membranous, 2-keeled, retuse — Tufted annuals 

 or perennials, with spike-like panicle. 



P. Foxii, Post. 0? .00 to .1, pubescent; 

 culms geniculate-ascending. Leaves narrow- 

 linear, convolute, mouth of sheath short-bearded. 

 Panicle cylindrical, .02 to .03 long, .000 broad; 



113 



Fig. 398. 



(a) Spikclct of 



(6) Lower pale G diamcteni. 



