132 MR. G. BENTHAM ON GRAMINEE. 
extreme readiness with whieh some species hybridize with the 
cultivated wheats has given rise to the suggestion, strongly advo- 
cated by some, positively rejected by others, that it is in some of 
the common species of ZEgilops that we must look for the original 
of our cereal wheats. 
The second subtribe, Lepturec, is characterized by the slender 
spikes and the spikelets solitary at the notches, each with only 
one or rarely two flowers. We refer to it five genera, placed by 
Kunth and some others in Rottboelliex, from which they differ in 
the outer empty glumes, when present, persisting below the arti- 
culation of the rhachilla. 
5. Leprurvs, Br., including PAoliurus, Trin., has six species, 
five of them with the ordinary geographical range of the tribe, 
the sixth, L. repens, Br., exclusively Australasian or South Pacific 
and maritime. They are distinguished in the subtribe by the 
rigid outer empty glumes, one or two in number, much longer 
than the hyaline flowering glume, thus showing the nearest 
approach to Rottboelliez. They differ from each other sufficiently 
to have been referred by different botanists to different genera. 
L. cylindricus, Trin. (L. subulatus, Kunth), included by Link in; 
Ophiurus, by Reichenbach in Monerma, has one outer empty glume 
and one flower with no empty glume above it. The Australasian 
L. repens, a much larger plant than any of the others, has one 
outer empty glume, one flower, and above it a glume either 
empty or enclosing a palea, but no flower. L. persica, L. incur- 
vata, and L. filiformis, Trin., have two lower: empty glumes, one 
flower, and no empty glume above it. ZL. pannonicus, Kunth, 
forming Trinius's genus Pholiurus, and referred by T. Nees to 
Ophiurus, has two outer empty glumes and two perfect flowers. 
6. Psınurus, Trin. (Monerma, Beauv., partly, Asprella, Host 
but not of Willd.), is a single annual, near Lepturus, but with 
only one minute empty glume, a single narrow and awned flower- 
ing glume, and only one stamen in the flower. 
7. Narpus, Linn., is a single well-known small perennial, the 
position of which in the system is rather puzzling. The spikelet 
has only one flower without any empty glumes below it or pro- 
longation of the rhachilla above it, which might have decided its 
relationship either to Panicaceæ or to Poaceæ, and its long simple 
style might indicate an affinity to some Panice& or to Seslerie& ; 
but on the whole it seems nearest allied to the Lepturex, a sup- 
position which might be confirmed, if we regard the rather pro- 
