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Lrizopyrum pungens (Rupr.), under which name they were dis- 
tributed. Last year Dr. Palmer collected the same grass in the 
vicinity of Acapulco, which he discovered in 1890 on the seashore 
in Lower California, and also another species which proves to be 
the true /ouvea straminea of Fournier, as determined by a com- 
parison with the type. WhatI believe to be the male plants of 
the same species were also found, and from material gathered it 
has been possible to certainly identify Fournier’s species, to ascer- 
tain that the grass of Palmer’s earlier collection represents a dis- 
tinct species of the same genus and also to determine with reason- 
able certainty that the male plants of the latter are the Brizopyrum 
pulosum of Presl. 
From a study of the material now in hand, it appears to me 
that Fournier and others have heretofore misunderstood the struc- 
ture of the female inflorescence. What has been described as a _ 
terminal, cylindrical and acute spike appears to me to be a 2 to 
4-flowered spikelet with a remarkably developed rachilla in which 
the florets are embedded, the whole simulating in some degree 
the spikes of Monerma or Lepturus. These spikelets are lateral, 
sessile and articulated with the main axis, from which they readily — 
separate at maturity. They are subtended by and partly enclosed 
within the leaf-sheath, from whose axil they originate, and there 
is a strong and well developed prophyllon on the rachis of the 
spikelet, above which is the articulation. This position sug- 
gests that what we here term a spikelet may be only a modified 
branch (but spikelets of the more familiar type are in reality mod- 
ified branches), and the articulation of this with its own axis and 
the peculiar structure of the female flowers does, I think, warrant 
the use of the designation here given. These spikelets are with- 
out empty glumes, unless the leaf subtending them be regarded 
as a glume. In the staminate spikelets also the empty glumes 
are often entirely wanting, although occasionally we find one, and 
more rarely two, present. The glume which covers the female 
flower, called “ e/uma exterior” by Fournier, is really a flowering 
glume with its edge grown firmly to the rachilla for about one- 
half its length in /owvea straminea, the upper portion being free, 
but the edges so extended and grown together as to form a closed — 
cavity, having a small aperture only at the apex, through which 
