194 BOTANY OF CKOP PLANTS 



Staminate Spikelet. — The stalked spikelet is narrower, and 

 more pointed than the fertile one. It is two-flowered. It is 

 subtended by two leathery glumes. Irnmediately within 

 this pair is the lemma of the sterile flower of the spikelet. 

 Then comes the lemma of the staminate flower; it may be 

 short-awned or awnless; the palet of this flower is absent. 

 The lodicules and stamens resemble those of the fertile spike- 

 let. There is no pistil. 



Opening of Flowers and Pollination. — Flowers do not be- 

 gin to open on the inflorescence until the latter is entirely out 

 of the leaf sheath. The first flowers to open are those near 

 the tip of the head. Blooming proceeds from the tip down- 

 ward. As a rule, flowers at the tip of an inflorescence have 

 shed their pollen, and closed, when the lower flowers of the 

 head are just beginning to bloom; Flowers on branches be- 

 longing to one whorl are usually in about the same stage of 

 blooming. In nearly all cases, the sessile spikelet of a pair is 

 the first to open. The stalked spikelets may sometimes fail to 

 protrude their stamens. Most of the flowers open in the early 

 morning; there is but very slight amount of blooming during 

 the day. The stigmas may protrude to a shght extent first. 

 (Fig 7 2) . They are followed by the anthers. When the flower 

 starts to open, the whole process takes place within from ten 

 to fifteen minutes. The spreading of the glumes, and the 

 emergence of anthers and styles may be so rapid in some in- 

 stances as to be seen with the hand lens. The stamens ex- 

 tend their full length, as a rule, and the anthers swing on long 

 filaments. In some cases, however, the anthers never fully 

 project from between the glumes,, but shed their pollen, and 

 dry up, half or one-fourth caught by the glumes. When the 

 anthers are partly out, the stigmas are fully protruded. No 

 sooner are the anthers visible than they begin to dehisce by 

 two narrow sKts at the tip only. The stigmas and pollen- 



