492 
The Ohio Naturalist. 
[Vol. XII, No. 5, 
(3). Spikelets with but one perfect flower, or monosporan- 
giate; always in panicles or racemes, not in rows. 
a. Spikelets with 4 or more glumes. 
(a) . Third glume enclosing a perfect flower just 
above the empty glumes ; palet of the perfect 
flower usually 2-nerved. Tribe, Agrostidece. 
(b) . Fifth glume enclosing a perfect flower on the 
top of the spikelet ; palet of the perfect flower 
usually 1 -nerved or nerveless. 
Tribe, Phalar ideas. 
b. Spikelets usually with but 2 glumes, or the lower 
empty glumes reduced; spikelets often mono- 
sporangiate. Tribe, Oryzece. 
II. Spikelets 1 " usually 2-flowered or by degeneration 1 -flowered; 
rachilla articulated below the empty glumes which are thus 
deciduous with the flowers; spikelets more or less dorsallv 
compressed; aerial stems annual. 
Subfamily, Panicatae. 
1 . Flowering glumes, at least of the perfect flowers, similar in 
texture to the empty glumes, or frequently coria- 
ceous or chartaceous (indurated), never thin 
and hyaline. 
a. Flowering glumes of the perfect flowers chartaceous or 
coriaceous, very different from the empty glumes. 
Tribe, Panicea. 
b. Flowering glumes membranous. 
(a) . Inflorescence paniculate, spikelets deciduous 
singly from the ultimate branches; first empty 
glume usually smaller and narrower than the rest. 
Tribe, T risteginece. 
(b) . Inflorescence spikate; spikelets deciduous singly 
or in groups; first empty glume usually larger 
than the rest, the second one often spiny. 
Tribe, Zoysiece. 
2. Flowering glumes thin and hyaline, much more delicate in 
structure than the thick-membranous or coriaceous 
empty glumes. 
a. Spikelets in pairs, one usually sessile the other pedi- 
cellate, the sessile spikelet with a perfect flower, 
the pedicellate one with a perfect, staminate, or 
sterile (vestigial) flower; lemmas of the perfect 
flowers usually awned. Tribe, Andropogonece. 
b. Spikelets monosporangiate, in separate inflorescences 
or in different parts of the same infloresence, the 
earpellate portion or inflorescence below, the 
staminate above; lemmas awnless. 
Tribe, Maydece. 
