MORPHOLOGY OF THE FLORAL ORGANS 121 
tribe Panicee. In the series Poxoidee the pedicel is 
usually not jointed below the spikelet but the rachilla 
may be articulated below the first lemma, so that at 
maturity the upper part of the spikelet falls away leaving 
the glumes. There are exceptions in both groups. In 
many species of Eragrostis the rachilla remains attached 
to the pedicel and the lemmas fall away. 
The pedicel is sometimes differently developed in 
the same inflorescence, as in many Andropogonez, where 
the spikelets are in pairs, one being sessile and fertile, 
the other pediceled and bearing a staminate spikelet or 
only a bract which may represent a glume, or the spikelet 
may be aborted, the pedicel persisting as a naked stalk. 
The pedicel may be grown fast to the axis as in Rytilix 
and Manisuris. 
152. The glumes are the 2 empty bracts at the base of 
the spikelet and are called respectively the first and 
second glume. They usually differ in shape, nervation or 
texture or in other particulars from the lemmas above 
them. Frequently the first glume is smaller than the 
second and often has fewer nerves. Sometimes this 
reduction goes so far that the first glume is only a vestige 
or it may be altogether wanting. Syntherisma shows 
various stages in the elimination of the first glume, and 
in Paspalum the first glume is generally absent or repre- 
sented by a slight ridge. However there are species of 
Paspalum in which the first glume may be present or 
absent in the same raceme (P. distichum, Paspalum § 
Dimorphostachys). The first glume in Eriochloa is usually 
represented by a cup-shaped ridge below the normally 
shaped second glume, but is present in certain species. 
Both glumes are absent in a few genera, such as Reimaro- 
chloa and Homalocenchrus. 
