152 STUDY OF COMMON PLANTS. 



XIX. THE IRIS FAMILY. 



MATERIAL REQUIRED. 



Blue flag, Iris versicolor, L., in flower. 

 Blue-eyed grass, Sisyrinchium angustifolium, Mill. 

 Cultivated Iris, Gladiolus, and Crocus. 



BLUE FLAG. Iris versicolor, L. 

 Distribution and General Characters. 



I. Does the plant manifest a decided choice of locality? 

 Is there anything to indicate whether it is an indigenous 

 species ? 



II. Notice the form and arrangement of the leaves. 

 They are described as equitant. When studying other 

 species recall this peculiarity, and observe whether it is 

 characteristic of the family. How do the bracts that 

 subtend the flowers compare -with the stem leaves? 



III. Write a description of the plant as a whole, includ- 

 ing rootstock, stem, and leaves. 



Flower. 



I. Study first the morphological characters. 



1. Look over the flower, whorl by whorl, and see 



whether you recognize each part. 



2. Determine the plan. How many divisions of the 



perianth are there? How many stamens and 

 styles? Does the plan of the flower differ in any 

 particular from that of the lily (or Trillium)? 



