694 



A TEXT-BOOK OF BOTANY. 



;. ACANTHACE^; OR ACANTHUS FAMILY. The 

 plants are mostly tropical perennial herbs, or shrubs with opposite 



T"lG. 384. Common Plantain (Plantago major). A very familiar weed found along 

 waysides and in poorly kept lawns. The leaves are clustered, lying near the ground, broadly 

 elliptical and with prominent parallel veins. The flowers occur in long, dense spikes which 

 give rise to small, capsular fruits, being sometimes employed as a green bird food. After 

 Brown. 



leaves ; in the mesophyll or epidermal cells and parenchyma of the 

 axis occur cystoliths. Several genera are represented in the 

 United States, one of which, Ruellia (Ruellia ciliosa), is the source 



