MB. &. BENTHAM ON GKAMINEiE. 131 



and close together in a short dense spike, the narrow empty 

 glumes nearly equal-sided and keeled. Two species, A. villosum 

 (Secale villosum, Linn., Saynaldia, Schur) and A. hordeaceum, 

 Boiss., form the proposed section Dasypyrum, Coss. and Dur. 

 {Pseudosecale, Gren. and Godr.), differing slightly from the other 

 species in the empty glumes rather unequal-sided, and one lateral 

 nerve on one side of the keel very frequently as prominent as the 

 keel itself, giving the glume the appearance of being two-keeled. 

 Heteranthelium, Hochst., from the Levant, is a species very near 

 A. {Eremopyrum) orientate, with a dense villous spike, and several 

 of the spikelets, especially near the base and apex of the spike, 

 often sterile with empty glumes. 



3. Sj3CAiiE, Linn., is now reduced to two species or perhaps 

 varieties, the cultivated Rye, of which S. montanum, Guss., is 

 supposed to be the original spontaneous form, and S. fragile, 

 Bieb. The genus differs slightly from the section Eremopyrum 

 of Affropyrum in the dense cylindrical spike, and in the spikelets 

 usually containing only two flowers. 



4. Teiticttm, Linn., excluding Affropyrum and including ^yi- 

 lops, can scarcely reckon more than ten botanical species ; the 

 most prominent character separating them from Agropyrum con- 

 sists in the shape of the spikelets not so flat, and especially in the 

 lateral nerves of the flowering glumes not conaivent, but remain- 

 ing parallel or nearly so, and either stopping short of the apex or 

 produced beyond it into distinct teeth or awns. There are three 

 rather distinct groups : — 1. The cultivated Wheats, of unknown 

 origin, in which the flowering glumes are keeled at the end and 

 sometimes from the base, and terminate in a single awn, the 

 lateral nerves usually barely reaching to the end of the glume. 



2. CrithoMum, Link, founded on T. monocoecmi, Linn. {T. boeoti- 

 cum, Boiss.), in which the spikelets have only one fertile flower, 

 and the flowering glume is keeled from the base and ends in 

 a single awn, T. bicorne, Torsk., with two or even three fertile 

 flowers and the lateral nerves of the flowering glumes sometimes 

 produced into short teeth, may be referred to the same section. 



3. ^gilops, Linn.< above forty published species, which Munro 

 reduces to seven or eight, differing from the cereal wheats in the 

 flowering glumes more rounded at the back and not at all keeled, 

 and in the lateral nerves of the flowering glumes often produced 

 into long awns, especially in the upper end of the spike. The 



