Grasses 



FIG. 40. Oats and yarrow. 

 <*, A cluster or "spikelet" of oat-blossoms; 6, a cluster or "head "of yarrow- 

 blossoms; c, a single oat-blossom with its enfolding ''glumes''- 

 yarrow-blossom with its attendant " bracteole " 



