92 ME. G. BENTHAM ON GEAMINEJE. 



straight awns to the flowering glume, besides the long rigid 

 twisted dorsal one, which, as well as the single flower, removes 

 the genus from the Pappophorese. 



37. Lagubtjs, Linn., is a well-known widely spread Mediter- 

 ranean grass, which, like Trisetaria, has two slender awns to 

 the flowering glume besides the more rigid dorsal one, but is 

 well marked by the capitate inflorescence, to which the long hairs 

 of the linear plumose empty glumes give a peculiar soft silky 

 aspect. 



Tribe IX. IsACHNEiE. 



This small tribe is a modification of the subtribe I proposed 

 in the ' Plora Australiensis ' under the name of Milieae, and which 

 I distinguished from AgrostesB by the absence of the dorsal awn, 

 and from Testucese by the single or two equal flowers in each 

 spikelet ; and I included in the group both Milium and Sporo- 

 bolus. Since I have worked up the , Agrostess of the northern 

 hemisphere, however, I find that the presence or absence of the 

 dorsal awn is much more uncertain than I had thought, that 

 Milium cannot be removed far from Oryeopsis, and that Sporo- 

 iolus must be referred back to Agrosteae. But there remain a 

 group of genera, nearly related both to Agrostess and to Avenese, 

 but never showing the dorsal awn so general in those tribes, 

 and enclosing in each spikelet two equal flowering glumes and 

 flowers, apparently inserted at the same point without any deve- 

 lopment of the rhachilla between them (except in Ccelachie) and 

 never any continuation beyond the flowers. The two fl.owers are 

 both hermaphrodite and fertile ; or occasionally only one of them, 

 usually the upper one, is female or sterile. The tribe thus limited 

 would consist of the following seven genera : — 



1. Peionachite, Nees, subsequently republished by the same 

 author under the name of Ghondrolcena, is a South-African annual 

 with an almost simple terminal spike, distinguished by the outer 

 empty glumes as long as the flowering ones, with a rigid pec- 

 tinately-toothed cartilaginous keel. Ktenosaohne, Steud., is most 

 probably the same plant. 



2. IsAOHNE, Br., comprises about twenty tropical or subtro- 

 pical species, chiefly from the Old World, but including a few 

 American ones, The small spikelets with the loosely paniculate 

 inflorescence and more or less hardened fruiting glumes give them 

 the appearance nearly of some species of Panicum, to which 



