Classification of Plants 



179 



contain flowers. For each flower there is one outer heart- 

 shaped rounded glume, also keeled, and an inner, much 

 smaller, flat, and two-nerved glume or pale a (the flowering 

 glumes are called paleae to distinguish them from the empty 

 glumes), which clings closely to the grain. When the three 

 stamens are ready to shed their pollen, the glumes open, and 

 the slender filaments hang out the swinging anthers. The 

 ovary has two feathery stigmas. The fruit, a caryopsis, is an 

 achene in which the ovary becomes attached to the seed-coat, 



Fig. 185. — I. Expanded spikelet of the Oat, with a fertile and barren flower, FS ; G, 

 glumes ; Ve, outer pale, with awn, A ; P/, inner pale ; within are the feathery 

 stigmas. II. Fertile flower with outer pale removed. (From Thome and Bennett s 

 " Structural and Physiological Botany.") 



so that they seem like one covering. Between the ovary 

 and the outer glume there are two very small bodies called 

 lodicules. 



In the bamboos there are three, longer than the ovary, which suggests 

 that the grasses may once have had a perianth. The showy spikelets nod 

 gracefully on slender pedicels, whence the name, meaning, in Greek, to 

 slumber. 



Large as the order is, the flowers are very similar in the different 

 genera. The outer glume is awned in the oat (Avena) ; that is, it has a 

 long twisted spike extending from the midrib. The awn is common to 

 other genera. Rice has 6 stamens. In Coix, " Job's Tears," and maize 

 the flowers are monoecious. The stamens here are toward the top of the 

 panicle, and the pistillate flowers below. In maize the stigma is neither 



