Plagiosetum.} CXLIV. GRAMINER. 495 
out i in. l he bristles not plumose, united a 
and spikelet. Involuere not completely surrounding the spikelet, 
a ong, t ris d at the base 
into 3 or 4 slightly flattened branches with the minor branches or 
Central Australia. Cooper's Creek, Howitt’s Expedition ; Alice Springs, Giles. 
Occasionally but rarely the principal branch of the involucre is rather more flattened 
and ends in a second spikelet, but the articulation is below the involucre as in 
Pennisetum, not under each spikelet as in Setaria. 
7. PENNISETUM, Rich. 
(Gymnothrix, Beauv). 
9: some modern botanists, be placed in two different genera, founded on the nature of 
the involucre, and neither belong to the typical form with the inner bristles plumose 
and the outer ones simple. 
Involucral bristles numerous, all simple, surrounding the 
Spikelet in several rows. . . e © + + + «4 
Involucral bristles 6 to 10, all plumose at the base, closely 
surrounding the spikelets . . s's + + + + + + 
1. P. compressum. 
2. P: arnhemicum. 
dense spike of 3 to 6 in., consisting of numerous very unequal bristles, 
he inner more rigid ones varying from 3 to 1 in., the outer ones much 
shorter and finer, mostly minutely scabrous-ciliate but none of them 
