MANUAL OF THE GRASSES OF THE UNITED STATES 



765 



sometimes reduced to a pedicel or wanting; glumes membranaceous, 

 obscurely nerved; lemma and palea hyaline; stamens 3; pistillate 

 spikelets 3 together, 1 fertile and 2 sterile at the base of the inflo- 

 rescence; glumes of fertile spikelet several-nerved, hyaline below, 

 chartaceous in the upper narrow pointed part, the first very broad, 

 infolding the spikelet, the margins infolded beyond the 2 lateral 

 stronger pair of nerves; second glume narrower than the first, keeled, 

 sterile lemma similar but a little narrower; fertile lemma and palea 

 hyaline; sterile spikelets consisting of a single narrow tubular glume 

 as long as the fertile spikelet, somewhat chartaceous. Tall branched 

 grasses with broad flat blades, the monoecious inflorescences numerous 

 on long, stout peduncles, these clustered in the axils of the leaves, 

 each inflorescence consisting of an 

 ovate or oval pearly white or drab, 

 beadlike, very hard, tardily decidu- 

 ous involucre (much modified sheath- 

 ing bract) containing the pistillate 

 lower portion of the inflo- 

 rescence, the points of the 

 pistillate spikelets and the 

 slender axis of the stami- 

 nate portion of the inflores- 

 cence protruding through 

 the orifice at the apex, the 

 staminate upper portion of 

 the inflorescence 2 to 4 cm 

 long, soon deciduous, con- 

 sisting of several clusters of 

 staminate spikelets. Type 

 species, Coix lacryma-jobi. 

 Name from Greek koix, a kind of 

 palm, applied by Linnaeus to this 

 grass. 



1. Coix lacryma-jobi L. Jobs- 

 tears. (Fig. 1691.) Annual; culms 

 usually about 1 m tall; blades as much 

 as 4 cm wide; beads white or bluish- 

 white, globular or ovoid, 6 to 12 mm long. 

 O — Occasionally cultivated for ornament, escaped into waste places 

 in the Southern States; all tropical countries, introduced in America. 

 The beadlike fruits are used as beads and for rosaries. A garden form 

 (called by gardeners var. aurea zebrina) has yellow-striped blades. 



157. TRIPSACUM L. Gamagrass 



Spikelets unisexual; staminate spikelets 2-flowered, in pairs on 

 one side of a continuous rachis, one sessile, the other sessile or 

 pedicellate, similar to those of Zea, the glumes firmer; pistillate 

 spikelets solitary, on opposite sides at each joint of the thick, hard 

 articulate lower part of the same rachis, sunken in hollows in the 

 joints, consisting of one perfect floret and a sterile lemma; first 

 glume coriaceous, nearly infolding the spikelet, fitting into and 

 closing the hollow of the rachis; second glume similar to the first 



