CXLVIT. GBAMINE^. 911 



when mature, usually 5-nervecl, all the nerves or the outer side-nerves 

 often slightly excurrent, parallel, or at least not anastomosing. 

 Spikelets avvned or not. 



Spikelets in cylindric spike-like panicles ; spikelets not 



awned 42. Heleochloa. 



Spikelets in open or contracted many-flowered panicles ; 

 spikelets awned. 

 Spikelets subdigitately panicled at the top of a slender 



peduncle, laterally compressed ; stamens 2 43. Woodrowia. 



Spikelets terete, in branched panicles; stamens 3 44. Garnotia. 



Tribe 8. ZOYSIE.ffi. Mature spikelets falHug entire and singly or 

 in clusters. Floret 1. Ehaehilla not produced beyond the floret. 

 Glumes equal or the lower much smaller or suppressed. Floral glume 

 small, thinly membranous, 1-3-nerved. Spikelets in slender spiciform 

 panicles or racemes. 



Spikelets falh'ng in clusters of 2-4. 

 Spikelets fascicled. 



Fascicles secund on a broad articulate rhachis ; 



glumes 4 ; upper iiivol. -glume not echinate 45. Trachys. 



Fascicles all round a slender rhachis ; glumes 3 ; 



upper invol. -glume echinate 46. Tragus. 



Spikelets falling singly. 



Lower invol. -glume with pectinate margins ; upper 



invol. -glume spinulosely tuberculate ; glumes 3 47. Latipes, 



Invol. -glumes ueitlier pectinate nor tuberculate. 



Glumes 2 ; spikelets not awned 48. Zoysia. 



Glumes 3 ; spikelets with a long awn 49. Perotis. 



Tribe 9. SPOROBOLE.ffi. Involucral and floral glumes very similar. 

 Floret 1. iihachilla not (or rarely) produced beyond the fl.oret. 

 Upper floral glume membranous, acute or obtuse, not changed when 

 ripe,»l- or more or less distinctly 3-nerved, awnless, usually olive-green 

 or grey ; side-nerves, if present, delicate, evanescent above. Seed 

 often free in the delicate pericarp. 



Spikelets small 50. Sporobolus. 



Tribe 10. ERAGROSTEiE. Spikelets variously panicled, sometimes 

 spicate or subspicate. Florets usually numerous and far-exserted 

 from the glumes. Involucral and floral glumes somewhat similar in 

 general appearance. Floral glumes membranous or chartaceous, entire 

 or 2-3-cleft, 3-nerved, the nerve evanescent above or excurrent into 

 bristles ; side-nerves usually submarginal, glabrous or pubescent or 

 linely ciliate below. Palese often persistent or subpersistent. 



Floral glumes entire. 



Upper invol. -glume 3-nerved 51. Eragrostis. 



Upper invol.-glume 5-nerved 52. Haloiyrum. 



Floral glumes toothed 53. DiPiiACiiNB. 



Tribe 11. CHLORIDE.^. Spikelets usually in 2-ranked secund 

 spikes or spike-like racemes, rarely distinctly pedicellate and paniculate. 

 Florets 1 to many. Floral glumes usually membranous, truncate, 

 eraargiuate or toothed, 3-nerved ; nerves distant, subparallel, distinct, 

 percurrent or excurrent, and often ciliate all along, the lateral 

 submarginal (in Elmslne there are sometimes additional side-nerves 

 close to the middle nerve of the glume). Awn, if present, straight, 

 usually from a truncate or toothed tip. 



