ME. G. BENTHAM ON GEAMrfTEiE. 87 



genus, but in tte whole tribe of Agrostese, by the spikelets con- 

 taining occasionally two flowers (without awns or continuation of 

 the rhachilla) as in Isachnese and in some species of Aira and Gol- 

 podium ; but the small spikelets and carpological characters are 

 quite those of Sporobolus. 



There remain for the ETTAGEOSTEiE, or fourth and last subtribe 

 of Agrostese, about sixteen genera, of which the general character 

 is a dorsal usually twisted awn on the flowering glume, the grain 

 neither so closely enveloped in the fruiting glume as in Stipese, 

 nor so readily exposed as in SporobolesB, and the spikelets usually 

 small, loosely paniculate, very rarely condensed into a head as in 

 Phleoideae ; but there are exceptions to every one of these charac- 

 ters, and the limits of the larger genera are so vague as to render 

 this portion of the genera of Gramineae the least satisfactory of the 

 whole series. Of the sixteen following genera, the first seven 

 show none of that continuation of the rhachilla beyond the flower 

 which in the others takes the form of a glabrous or hairy bristle 

 rarely reduced to a mere tubercle ; the last four of the series, as 

 well as Triplachne, have, besides the dorsal awn, two or four teeth 

 to the glume, sometimes produced into straight awns. A few spe- 

 cies or monotypic genera have no awn to the flowering glume, 

 but otherwise in the structure of the spikelet are nearer to Agrostis 

 than to Sporoholus. 



20. Epioampes, Presl, about sixteen species from Mexico and 

 the South-American Andes, probably reducible to about two 

 thirds of that number, is a genus most embarassing to the syste- 

 matist ; for it seems to connect Muehlenbergia and Sporoholus with 

 Agrostis. The chief general feature is the long narrow dense 

 panicle with very numerous rather small spikelets, the awn 

 of the flowering glume, when it exists, much smaller, than in 

 Muehlenbergia and often not quite terminal ; the unawned species 

 distinguished from Sporobolus by the fruiting glume and grain 

 nearly those oi Agrostis, and from the latter genus by the inflo- 

 rescence and by the awn when present being very small and 

 almost terminal. Several of the published species, however, are 

 unknown to me ; and a further study may require considerable 

 modification of the generic character and limits. Orypsinna, 

 Fourn., which appears inseparable from Epicampes, is founded 

 on the E. maoroura (Cinna macroura and G. striata, Kunth), a 

 Mexican species remarkable for the very long, narrow, almost 

 spikelike panicle. Cinna macroura, Thurb., from California, is a 



