FLORA OF ADEN . 
377 
Panicle varying from spike-like to effuse. Spikelets 1 -flowered, narrow, 
panicled, rhachilla disarticulating above the glume, not produced. 
Glumes usually persistent, narrow, 1-3-nerved, muticous or mucronate, 
awnless. Valve convolute, cylindric or oblong cylindric, 3-nerved, 
awned, rather rigid, tips gradually tapering or minutely bilobed, 
sometimes jointed at or above the middle; callus villous, shortly bearded, 
usually pungent; awn nearly always tripartite from the base or above 
the simple base, very rarely simple, continuous with the valve or 
disarticulating from it or deciduous with a portion of the valve, foot 
straight or twisted, bristles plumose or the lateral or all naked. Palea 
small, oblong, 2-nerved or nerveless. Lodicules 2, finely nerved. 
■Stamens 3. Ovary glabrous; styles distinct, short ; stigmas plumose, 
laterally exserted, 
Grain slender, cylindric or oblong-cylindric, terete, sometimes 
grooved, lightly embraced by the valve ; hilum linear, almost as long 
the grain ; embryo short or long. 
Species about 100. 
Distribution :*~In the dry and warm regions of both hemispheres 
Awn tripartite from the base : 
Glumes not equal : 
Stems J-3 ft. high . . . . • . 1. A. Adscensionis. 
Stems up to 4 inches high . . . . . 2. A. pumila. 
Glumes equal • . . . . • . . 7. A. mutabilis var„ 
Awn feathery : 
Leaves rigid : 
Sheath glabrous . 
Sheath not glabrous . 
Leaves flexuous : 
Lower glume longer than the upper 
Lower glume shorter than the upper 
. 3. A. brachypoda. 
. 6. A. plumosa. 
. 5. A. hirtigluma. 
. 4. A. paradisea. 
1, Aristida Adscensionis Linn. Sp. PL ed. I, p. 82 ; Kurtth Enum. 
PI. I, 190 ; Willd. Sp. PL I, 458; Trim et Rupr. Stip. 138 ; Steud. Syn. 
PL Glum. I, 139 ; Anders. Journ. Linn. Soc. V, Supplem. p. 39 ; Boiss. 
FI. Or. V, 491 ; Batt. et Trab. FI. d’Alg. 56 ; Baker FI. Maurit. 450 
Durand & Schinz Consp. FI. Afr. 799; Hook. FI. Brit. Ind. VII, 224; 
Cooke FI. Bomb. Pres. II, 1008. 
Aristida paniculata Forsk. FI. Aegypt.-Arab. 25 (?)L 
Aristida americana Linn, in Arnoen. Acad. V, 393 (not Swartz). 
Aristida gigantea Linn, FI. Suppl. 113. 
Aristida depressa Betz. Obs. IV, 22. 
Aristida cserulescens Desf. EL Atlant. I, 109, t. 21, fig. 2 ; Sebum. 
& Thonn. Beskr. Guin. Pl. 47 ; Trin. Sp. Gram. Ic. t. 313. 
Synonymy after Stapf. 
