371 
gular genera of the order, and also to understand the limits of the two great 
tribes into which I have proposed to subdivide it. One of these tribes, which 
may be called Panicese, comprehends Ischsemum, Holcus, Andropogon, An- 
thistiria, Saccharum, Cenchrus, Isachne, Panicum, Paspalum, Reimaria, An- 
thenantia, Monachne, Lappago, and several other nearly related genera ; and 
its essential character consists in having always a locusta of two flowers, of 
which the lower or outer is uniformly imperfect, being either male or neuter, 
and then not unfrequently reduced to a single valve. Ischaemum and Isachne 
are examples of this tribe in its most perfect form, from which Anthenantia, 
Paspalum, and Reimaria, most remarkably deviate, in consequence of the sup- 
pression of certain parts : thus Anthenantia (which is not correctly described 
by Palisot de Beauvois) difi’ers from those species of Panicum that have the 
lower flower neuter and bivalvular, in being deprived of the outer valve of its 
gluma ; Paspalum differs from Anthenantia in the want of the inner valve of 
its neuter flower, and from those species of Panicum whose outer flower is 
univalvular, in the want of the outer valve of its gluma ; and Reimaria differs 
from Paspalum in being entirely deprived of its gluma. That this is the real 
structure of these genera may be proved by a series of species connecting them 
with each other, and Panicum with Paspalum. The second tribe, which may 
be called Poacese, is more numerous than Panicese, and comprehends the 
greater part of the European genera, as well as certain less extensive genera 
peculiar to the equinoctial countries ; it extends also to the highest latitudes 
in which Phsenogamous plants have been found ; but its maximum appears to 
be in the temperate climates, considerably beyond the tropics. The locusta 
in this tribe may consist of 1, 2, or of many flowers ; and the 2-flowered ge- 
nera are distinguished from Panicese by the outer or lower flower being 
always perfect, the tendency to imperfection in the locusta existing in oppo- 
site directions in the two tribes. In conformity with this tendency in Poacese, 
the outer valve of the perianthium in the single-flowered genera is placed 
within that of the gluma, and in the many-flowered locusta the upper flowers 
are frequently imperfect. They are, however, some exceptions to this order 
of suppression, especially in Arundo Phragmites, Campulosus, and some other 
genera, in which the outer flower is also imperfect : but as all of these have 
more than two flowers in their locusta, they are stiU readily distinguished 
from Paniceae.” Brown in Flinders, 580. 
According to this view, in a locusta of several florets, the scales at its 
base, or glumes, are bracts, and each floret consists of a calyx formed of one 
sepal remote from the rachis, and two cohering by their margins and next the 
rachis ; the little hypogynous scales are the rudiments of two petals, and the 
stamens alternate with these in the normal manner. This may be rendered 
more clear by the following diagram. 
B 
