CLASSIFICATIOX OF AXGIOSPERMS. 225 



A. CLASS MONOCOTYLEDONS. 



The Monocotyledons are mainly distinguished as follows : 

 The embryo has only one cotyledon; the leaves are mostly scat- 

 tered and parallel-veined ; the fibro-vascular bundles of the stem 

 are of the closed type, and the flowers are typically trimerous. 



L ORDER GRAM IN ALES OR GLUMIFLGR^. 



This order is composed of the two families, grasses (Gram- 

 ineae) and sedges (Cyperacese). 



a. GRAMINE^ OR GRASS FAMILY. The plants of this 

 family are nearly all herbs having cylindric, generally hollow 

 culms with swollen nodes. The leaves are exactly alternate, and 

 have long sheaths which are split or seldom closed, tubular, and 

 nearly always with a distinct ligule. The flowers are mostly 

 hermaphrodite and borne in spikelets with alternate floral-leaves, 

 the spikelets themselves being borne in spicate or paniculate 

 inflorescences. Each spikelet (Figs. 125, 126) consists of two 

 (seldom more) empty glumes, which are the lowest floral-leaves 

 in each spikelet : a varied number of flowering glumes, frequently 

 awned or toothed, which follow inside the empty glumes, and 

 each of which subtends a short branch (the rhachilla), the latter 

 bearing an adorsed fore leaf (the pale), which is generally two- 

 keeled and two-toothed, enclosing two minute scales (lodicules) 

 and the flower. The flower has mostly three stamens (there be- 

 ing six stamens in Oryza and Bambusa), with the anthers versa- 

 tile, and a simple gynaecium consisting of one carpel having two 

 styles and a plumose stigma. The ovary is unilocular with one 

 ascending or pendulous ovule. The fruit is a nut (grain 

 caryopsis), the seed being always firmly united with the thin 

 pericarp (except in Sporobolus, Eleusine, etc.). The embr^'o 

 is situated at the base, on the outer convex surface of the seed, 

 outside the endosperm. On germination the cotyledons remain 

 in the seed. 



The endosperm contains numerous starch grains and oil, while 



15 



