Grasses 161 



As grass-flowers send their pollen abroad only by 

 the wind, they have no need to lure insect messen- 

 gers, and hence have no striking colors, and, in 

 most cases, no perfume. They are generally very 

 small, and are massed together in compact groups, 



FIG. 39. Ligula of millet-grass. 

 (From the Vegetable World.) 



which live in close propinquity to other groups, 

 forming large floral communities. 



The oat of commerce is a typical grass, and 

 from a study of its parts one can gain knowl- 

 edge on the structure of grasses in general. 



To a casual glance there is little difference be- 



