E. J. BUTLER. 3 
between individual ears, it is more than probable that changes 
other than those described will be found on further search. 
1. The bristles of the involucre are very often hypertrophied, 
the hypertrophy affecting some only of the bristles (plate I, 
fig. 4). These are enlarged into tough, simple spines, usually 
non-plumose, ribbed, and showing various degrees of longitudinal 
torsion. They may be one inch long, by one-sixteenth of an inch 
thick, and may be flattened, round or angular. The upper part 
is sometimes spirally twisted, corkscrew-like. The bristles are 
also transformed in some cases into leathery, brown, flattened or 
contorted bodies, but they never show any approach to a leaty 
structure. 
2. The pedicel sometimes bears two spikelets, the lower 
being laterally seated and sessile, a little way above the involucre 
(plate Il, fig. 3). Only two spikelets have been seen thus, 
arising from the one rachilla. 
3. The number of florets on a spikelet 1s sometimes increased 
to three or four (plate II, fig. 3, upper spikelet). One or two of 
these may remain as mere aborted buds, usually at the lower 
part of the rachilla. 
4. In the individual spikelets the lower glumes I and II 
are never altered. As in normal ears they are often minute, and 
the lower usually difficult to see, and sometimes suppressed. The 
succeeding glumes III and IV, with their enclosed palez, are some- 
times unaltered. More usually they are elongated, sometimes to 
over an inch in length (plate II, figs. 2, 3,5). They never lose 
their character as glumes, and no division into sheath and blade 
was observed in any case, though they are occasionally virescent 
and usually softer and more membranous, than normally. 
Torsion, particularly of the wpper part, often occurs ; and some- 
times the glume is split into segments as a result of a local action 
of the parasite, which will be more fully described under the leaf 
alterations to be mentioned below. 
5. The lodicules are unaltered or suppressed. 
6. The stamens are variously modified (plate II, fig. 6) or 
suppressed. The changes affect both the filament and anther. 
