MONOCOTYLEDONS. 



49 



LESSON X. 



Class n-Angiosporm.. 2 Sub-Classes [I l'^llZ:^^^^t'''- 



Sub-Class I. E3S"I)oqbns. Monocotyledons. 



82, 83. Ovary Free : Grasses. 84, 85. Sedges. 

 86. Wood-Rush to Lily. 87. Spadix-bearers. 

 88. "Water-Plantains. 89. Ovary Adherent : 

 Eel-Grass to Orchis and Banana. 90. En- 

 dogenous Growth. 91. Specialization. 



82. Division I. Ovary Free (Su- 

 perior). — The Grasses stand first (low- 

 est) in the Monocotyledons. They 

 have fibrous roots ; simple stems, 

 which are usually jointed and often 

 hollow ; sheathing paralkl-veined, and 

 simple leaves (Fig. 51). The ovule 

 here is covered by an ovary ; the 

 embryo has one cotyledon. The 

 flowers are often monoclinous, some- 

 times diclinous, as in Indian Corn, 

 and sometimes polygamous (diclinous 

 and monoclinous on the same plant), 

 as in Fig. 51. The male flowers have per- 

 fect stamens, with filaments and anthers ; 

 the female flowers have perfect pistils, with 

 ovary, style, and stigma. The flowers grow 

 in small clusters called Spikekts (Fig. 52, A). 

 These spikelets are in larger clusters called 

 Spikes, or Ears, and the spikes are often 

 arranged in a loose plume called a Panicle 

 (Fig. 51, a). Each spikelet has an Involucre, 

 or cover, of two bracts called Glumes, or 

 Husks (Fig. 52, A, g) ; each flower has two 

 bracts called Palece, or Chaff (Fig. 52, A, 

 pe, pi) ; the outer palea is often furnished ^^^ ^^ _^ 

 with a bristle called an Awn (A, a). The j^ie of wnd oats 

 -flower itself (Fig. 52 B) has an imperfect vacmm), a gmse ai- 

 perianth (which is rarely wanting) ; it con- siem, roots^teaV. ''' 

 d 5 



