258 



MONO CO T YLED ONS. 



Topic III : Monocotyledons with a glume subtending 

 the flower (Glumiflorae). 



504. Lesson III. Grass family (gramineae). Oat. — As a 



representative of the grass family (graminese) one may take the 

 oat plant, which is widely cultivated, and also can be grown 

 readily in gardens, or perhaps in small quantities in greenhouses 

 in order to have material in a fresh condition for study. Or we 

 may have recourse to material preserved in alcohol for the dis- 



Fig. 330. Fig. 331. Fig. 332. 



Spikelet of One glume re- Flower opened 



oat showing moved showing showing two palets, 



two glumes. fertile flower. three stamens, and 



two lodicules at base 



of pistil. 



Fig. 334- 

 _. Flower of 



Fig. 333- oat, show- 



Section show- ingthe upper 

 ing ground plan paletbehind, 

 of flower. », axis, and the two 

 lodicules in 

 front. 



section of the flower. The plants grow usually in stools ; the 

 stem is cylindrical, and marked by distinct nodes as in the corn 

 plant. The leaves possess a sheath and blade. The flowers 

 form a loose head of a type known as a panicle. Each little 

 cluster as shown in fig. 330 is what is a spikelet, and consists 

 usually here of one- or two fertile flowers below and one or two 

 undeveloped flowers above. We see that there are several 

 series of overlapping scales. The two lower ones are "glumes," 



