MONOCOTYLEDONS. 



299 



LODICULES . 



FLOWERING 

 GLUME 



OUTER GLUMES 



Fig. 118. Diagram of a Grass Spikelet. 



which is most marked in the upper " internodes," is largely 

 due to the active growth of the soft parts of stem just above 

 each node the parts 



enclosed in the leaf- STERILE FLOWERS-. 

 sheaths though 

 elongation also occurs 

 in all parts of each 

 " internode." Since 

 the stem grows in 

 width as well as in 

 length, the inner tis- 

 sue is torn and the 

 stem becomes hollow, 

 except at each node, 

 where a solid parti- 

 tion remains. The 

 growth in length is 

 greatest in the upper- 

 most " internode " 

 (above the highest 

 leaf), which carries up the inflorescence or " spike." 



About the beginning of June the sheath of the highest 

 leaf swells up, owing to the growth 

 of the " spike " which it encloses, and 

 in about a fortnight the flowers are 

 mature and the spike emerges from 

 the sheath. The " ears " are arranged 

 in two opposite rows ; each ear is flat 

 and is attached to the axis of the 

 spike by its side, so that the whole 

 spike is four- sided (the flat ears of 

 Eye are attached by their edges, hence 

 the Rye spike is flattened). 



Examine a single ear and, begin- 

 ning at the base, note the two lowest 

 scales, nearly opposite each other, 

 hard, dry ; these outer glumes 

 enclose from three to five flowers 

 (usually three) arranged alternately 

 on opposite sides of the ear (Fig. 118). In each flower 

 (Fig. 119) note the two enclosing scales an outer scale 



Fig. 119. Flower of Wheat en- 

 closed in its two Scaly Bracts 

 or Glumes. 



