168 STUDY OF COMMON PLANTS. 



XVIII. THE LILY FAMILY. LILIACE^. 



MATERIAL REQUIRED. 



Yellow adder's-tongue, Erythronium Americanum, Ker., in flower. 

 Representatives of other conspicuous genera of this family, as for 



example : Convallaria, Ornithogalum, Smilacina, Uvularia, Lilium, 



etc. 



Taking any of the plants named above, when in full 

 bloom, examine the structure of the flower, studying it 

 whorl by whorl, as directed in the case of Trillium, Sec- 

 tion VI. 



Comparison of even a few genera of Liliacese is suiScient 

 to show very wide differences of external features. At 

 the same time the regularity and fixed plan of the flower 

 afford constant and distinctive characters by which the 

 immediate recognition of the family is assured. The 

 student, however, should compare the flowers of a num- 

 ber of different species until their morphology is perfectly 

 familiar. This is the more important, inasmuch as the 

 flower of the Liliaceae serves as a type with which to coni- 

 pare the modified flowers of a number of related families 

 of monocotyledons. 



The family includes about sixteen hundred species, in- 

 habiting chiefly the temperate and warmer regions of the 

 globe. Many of the most pleasing and widely cultivated 

 ornamental plants, among them the tulip, lily, hyacinth, 

 and lily-of-the-valley, belong to this family. With them 

 are also included such medicinal plants as aloe, sarsapa- 



