MB. G. BENTHAM ON GtEAMINE^. 47 



from the pedicela below the spikelets. These setse are not 

 epidermal like the rigid hairs of many G-raminese, but, as ia 

 Pennisetvm, are supposed to be abortive branchlets of the 

 panicle, differing, however, from those of the latter genus by 

 being inserted below the articulation of the pedicel, so as to 

 remain persistent after the fall of the spikelet. The species are 

 very variable, and a large number have been described as distinct ; 

 they appear, however, to be reducible to about ten, three of which 

 are common weeds over a great part of the civilized world, and a 

 fourth ((S. italica) has been much cultivated as one of the Millets 

 of the Mediterranean region and the Levant. The genus was 

 first fully characterized by Beauvois in his ' Agrostographie,' 

 chiefly from the above-mentioned common weeds ; but he had pre- 

 viously published and figured, in his Elora of Oware and Benin, 

 under the name of Setaria longiseta, a plant which, as far as I can 

 judge without seeing the specimen, proves to be no Setaria at all, 

 but the Pennisetiwi {Becheropsis) unisetum, to which I shall pre- 

 sently refer. A few species or varieties of Setaria — one, for 

 instance, gathered by Hildebrandt in the Sandwich Islands, allied 

 to S. viridis, another, not uncommon in the Mexicano-Texan region, 

 allied to S. italica — have, like the variety of 8. glauca figured by 

 Trinius, 1. 195, the lower flower hermaphrodite as well as the upper 

 one, which is quite exceptional throughout all genera of Paniceae 

 except Bechmannia. laophorus, Schleoht. in LinnsBa, xxxi. 420, 

 was founded as a genus on TTrochloa uniseia, Presl, a Mexican 

 grass which we do not identify in our collections ; but Trinius 

 refers it to Panicum and Fournier to Setaria, with which Schlech- 

 tendal's description agrees very fairly. 



In our second or Gendhrus group of Panicese we include four 

 genera, chiefly tropical or subtropical, characterized by the 

 so-called involucre of bristles surrounding each spikelet or 

 sometimes each cluster of two or three spikelets ; this involucre, 

 supposed to represent abortive branchlets of the inflorescence, 

 being placed above the articulation of the pedicel, always falls 

 away with the spikelets ; the spikelets themselves are quite those 

 of Panicum, the inflorescence usually a simple spike raceme or 

 spikelike panicle, rarely a loose panicle of two or more pedunculate 

 spikes. 12. CEifCHErs itself, as reduced from the original Linnean 

 genus, consists of about a dozen species, both from the New and 

 the Old "World, two or three of them of very wide geographical 

 range, all characterized by the numerous bristles of the involucres 



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