MR. G. BENTHAM ON GRAMINEA. 49 
half that size. The involucres sometimes remain persistent after 
the spikelets have fallen away, and the filiform styles are remark- 
ably long; but many cultivated specimens and some East-African 
ones, possibly wild, offer so much variety in these respects, some 
passing quite into normal Penniseta, that it seems probable that 
the peculiarities of habit have arisen from long cultivation. The 
long styles united at the base occur in other species, amongst 
which P. (Gymnotrix) macrostachyum, Brongn., has on that account 
been proposed by Hasskarl as a genus, under the name of Sericura. 
Amphocheta of Andersson is a Galapagos species of the Gymnotrix 
group, with small spikelets in slender pedunculate spikes, forming 
a loosely paniculate inflorescence, very different from that which 
characterizes the greater number of Penniseta, but closely con- 
nected with them through the several varieties of P. ( Gymnotria) 
tristachyum, Kunth. In P. (Gymnotrix) unisetum, Nees, an 
African species proposed as a genus by Figari and De Notaris 
under the name of Beckeropsis, this peculiar inflorescence is 
carried still further, and the involucre is sometimes reduced to a 
single bristle (always above the articulation and falling away with 
the spikelet), though I usually find 2, 3, or even more bristles. 
It is probable that the plant figured by Beauvois as Setaria longi- 
seta is this same species of Pennisetum. Steudel’s proposed genera 
Catatherophora and Oxyanthe are normal species of Pennisetum 
(Gymnotrix). 
14. PraarosETUM, Benth.,is a single Australian species, which 
I characterized as a genus chiefly from its peculiar inflorescence 
and habit, which prevented my retaining it in Pennisetum without 
an extension of the generic character beyond what I felt justified 
1n proposing. 
15. PanaTHERIA, Griseb., is a single West-Indian species, 
Which proves to be identical with the Brazilian plant since pub- 
lished by Doell as a section of Leptachyrium of Panicum, but 
which is evidently more nearly related to Pennisetum. The 
inflorescence is a simple spike-like panicle, of which the numerous 
short articulate branchlets or pedicels are continued beyond the 
single spikelets into long awns or bristles, which fall away with 
the spikelet like the involucres of Pennisetum, thus forming in 
some sort a connexion between the Cenchrus group of genera and 
the following one. 
Our third or Chameraphis group of Panice» consists of seven 
small genera, loosely connected by a character which may be con- 
a =m e. (ov... 
