1 60 Gramineae. 



ORDER 88. — Gramineae. 



Flowers consisting of closely imbricated bracts or glumes usually perfect 

 (sometimes staminate or pistillate only, and sometimes neuter without either 

 stamens or pistil) one or more in a spikelet. Each spikelet consists of a pair 

 of bracts called the outer glumes^ within which are included the florets and 

 usually one or more empty glumes. Each floret consists of a pair of glumes 

 called the palea, enclosing the stamens and the ovary. Outer glumes usually 

 2 alternate. Palese 2 alternate, the outer one (sometimes termed \he Jlotverifig 

 glume) simple usually keeled often armed with an awn, the inner or upper 

 with two keels or nerves. Scales (or lodicules) minute, 2 or 3, sometimes 

 wanting. Stamens usually 3 hypogynous with versatile anthers. Ovary 

 superior, styles usually 2, stigmas feathery. Florets usually i — 3 in a spikelet. 

 Spikelets arranged in spikes, racemes, or panicles. The axis of the spike or 

 panicle is termed the rachis. When the spikelets are sessile along a common 

 stalk the inflorescence is a spike, and if the spikelets all turn one way (as in 

 Nardtcs stricta or Mat Grass) it is a one-sided spike. When the spikelets are 

 stalked the inflorescence is a raceme, or if the stalks are branched a panicle 

 either spreading (as in the Quaking Grass) or so close as to resemble a spike. 

 Stem cylindrical hollow and jointed. Leaves alternate with split sheaths. 



Stamens 2, ....... Anthoxanthum I, 



Stamens 3, 610 



610 Style and stigma i, . f . . t Nardus II 



610 Styles or stigmas 2, 6ii 

 611 Spikelets sessile — Inflorescence a true spike, 612 

 611 Spikelets stalked — Inflorescence a raceme 



panicle or spike-like cylindrical raceme, 613 



612 Spike compound, Panicum III. 



612 Spike simple, 614 

 613 Spikelets i -flowered, 615 



613 Spikelets with 2 or more flowers, 616 



614 Spikelets solitary, 617 



614 Spikelets in threes, Hordeum IV. 



615 Inflorescence a dense cylindrical spike-like panicle, 618 

 615 Inflorescence a lax panicle, . . . 619 



6i6 Florets all perfect, .... 620 



616 Florets only one perfect the rest neuter or imperfect, 621 

 617 Empty glumes 2, flowering glumes many, 622 

 617 Empty glumes I, flowering glumes many, .... Lolium V. 



618 Palea single awned, ..... Alopecurus VI. 



618 Palese 2 awnless, ..... Phleum VII. 



