GRASSES 297 
fleshy in the plum, but eventually becomes fibrous in the 
coconut. The coconut of the northern markets is the 
stone of the ovary wall, containing one large seed. This 
stone shows its tricarpellary structure by the ridges on 
its surface. 
539. Grasses (Graminales). In these plants (includ- 
ing several families) the stems and leaves have become 
elongated and markedly fibrous and tough. The flowers 
are of the Lily type but much reduced, and are clustered 
uniformly on slender axes into “spikelets.” In the 
Grasses proper (Family Poaceae) each flower is in the 
axil of an outer bract (flowering glume, flowering scale, 
lemma). The perianth consists of a scale-like, 2-keeled 
calyx (palet, palea) representing the two united posterior 
sepals (the third being absent) and of two (anterior), 
rarely three, small, fleshy petals (lodicules). Two whorls 
of three stamens each are present, or more often only 
the outer whorl. The pistil is tri- 
carpellary with two stigmas (very 
rarely three stigmas) and there is 
but one ovule in the single ovary 
cavity. 
540. The Bamboos are large, 
woody, hollow-stemmed tropical 
grasses, in which the corolla is pepe tae nr aiece 
trimerous, with the petals (lodicules) 
relatively large, the stamens are mostly six, and the 
pistil is frequently tristigmatic. In some bamboos the 
fruit is externally fleshy, while in others it is like that 
in the Brome Grasses. 
541. Brome Grass (Bromus) has a hollow herbaceous 
stem, and its large spikelets are several flowered; the 
corolla is reduced to two small petals (lodicules); the 
stamens are three, and the pistil has two feathery 
