424 GENERAL BOTANY 



IRIDACEAE (!EIS FAMILY) 

 IRIS VERSICOLOR (COMMON BLUE FLAG) 



Habitat and habit. The common wild blue flag of the spring 

 flora inhabits swampy land on the borders of streams and lakes 



canal. 



FIG. 270. Flower and reproductive structures of the iris (Iris versicolor) 

 A, flower and its parts ; B, ovary, style, and stigma ; (7, pollen tubes 



and is thus adapted to a hydrophytic habitat. Like many plants 

 of such habitats, however, its habit, represented by the form and 

 structure of its leaves and underground stem, is that of a xero- 

 phyte. This is probably due to the large percentage of organic 

 matter, including organic acids, in the water of the soil which 

 surrounds the roots of these plants in the marshes and swamps 

 where they live. 



The short aerial stem bears characteristic monocotyledonous 

 leaves and highly organized flowers. 



