6 
Indiana University Studies 
The spikelets are arranged in a panicle, whose primary 
branches are so reduced in structure that the whole inflores- 
cence appears to be a spike-like raceme. On the lower part of 
the rachis is usually a single pistillate spikelet, enclosed, with 
some other structures, in the spathe mentioned above. Above 
this, alternately arranged in pairs or groups of three, are 
thirty to a hundred staminate spikelets, each group consisting 
of sessile and pedicelled members (Figs. 1, 2). Rarely there 
may be as many as two or three pistillate spikelets in a row at 
the base of the inflorescence (Figs. 11, 15). 
The staminate spikelets are borne close together in a com- 
pact group, whose peduncle varies in length and thickness. 
The whole structure may be erect or nodding. The spikelets 
are usually erect on the rachis, but in some varieties (Fig. 2) 
they are definitely reflexed at maturity. The staminate spike- 
let and its flowers are the same as those of maize in significant 
structure (Fig. 3). 
The spathe surrounding the pistillate spikelet subtends and 
encloses an axillary group which is of great interest (Figs. 
4-7). This is really a short branch on which the pistillate 
spikelet is apparently terminal. Below this spikelet are two 
sterile pedicels attached at different levels, and doubtless at 
different nodes, and finally a prophyllum (Fig. 4).* The ster- 
ile pedicels are doubtless the homologues of two spikelets of 
the staminate groups of three. This observed structure is 
exactly in accord with the generally accepted interpretation 
of the groups of two or three spikelets which occur regularly 
thruout the Maydeae and Andropogoneae. It is interesting to 
note that here, inside a highly specialized enveloping organ, 
where we should expect to find extreme reduction of parts, 
there should occur, as a homologue of the group of three 
staminate spikelets, a branch so little reduced in structure as 
to show its prophyllum and its three spikelets apparently at- 
tached at different nodes. 
The prophyllum is unequally divided into two lobes at the 
top, and its two nerves are unequal in size. The two sterile 
pedicels are large and inflated or filled with a loose paren- 
chyma. Rudimentary bracts or floral organs often develop at 
their tips. 
* In one variety examined since this paper was written, two small rudiments seem 
to occur regularly on this axis above the prophyllum. It seems reasonable that these are 
the bracts subtending the two sterile pedicels. 
