64 MB. G. BENTHAM ON GEAMINEJ!. 



thinner than the lower or outer empty ones, usually hyaline, aad 

 often bearing a twisted or bent awn. The two spikelets of each 

 pair are either both of them perfect and fertile, or one of them 

 is male only or imperfect, or even quite rudimentary, and the 

 spikelets are often more or less surrounded by long silky hairs. 

 But to each of these characters there are exceptions in single 

 genera, which are retained in Andropogonese as agreeing with 

 them in most other respects. 



The plants of this tribe are for the most part tropical or sub- 

 tropical, although a few are found in more temperate regions, 

 chieily in the northern hemisphere. More than eighty genera 

 have at different times been proposed, which some botanists would 

 reduce to below twenty. Following as nearly as possible the 

 principles we have hitherto adopted, I have thought that the 

 following twenty-six may be admitted as fairly characterized, 

 referring them to four subordinate groups or subtribes — Sac- 

 ckarem, Arthraxece, Sotthoelliece, and Andropogonece proper. 



SaccTiareoB comprise seven genera, in which the two spikelets 

 of each pair are homogamous, both of them hermaphrodite and 

 usually fertile, and the inflorescence paniculate, excepting Pogor 

 natherum. 



1. Impeeata, Cyr., three or four species widely spread over the 

 tropical and subtropical regions both of the New and the Old 

 World, extending northwards to South Europe, China, and Japan. 

 In this and the following, Miscanthus, the branches of the panicle 

 are exceptionally inarticulate, showing an approach to the Tri- 

 steginete ; but the long silky hairs and the very much reduced 

 hyaline flowering glume and palea retain them in Andropogonese. 

 Munro has shown that the common American I. caudata, Anders., 

 is identical with the Old-World 1. ramosa, Anders. ; and I also 

 can find no difference between the two, any more than between 

 the American and the Old- World specimens of I. artmdinacea. 

 Pournier has, however, proposed to separate the American forms 

 of the two species generically under the name of Syllepis, on the 

 plea of their having the two lodicules connate into a single large 

 truncate one, which I have in vain sought for in several difierent 

 American specimens. It is possible that Fournier may have 

 considered the small truncate palea as a pair of united lodicules, 

 but, if so, they are precisely the same in the Old- World species. 



2. MiscAfTTHTJS, Anders,, as now limited, is a genus of eight 

 species, of which one is South- African, the others dispersed over 



