140 A NATURALIST IN THE GREAT LAKES REGION 



The yellow lady 's-slipper or moccasin flower can be recognized 

 from the illustration, for it is so unusual a blossom (Fig. 138). 

 Hepatica or liverwort (Fig. 139) has a three-lobed, dark, mottled 

 leaf; the pale pink or lavender blossoms come early in the 

 spring. May apple (Fig. 140) has large circular leaves, the stem 

 attached at the center. The large creamy white blossoms spring 

 from the fork of the stem, the blossoming plant always bear- 

 ing two leaves. Geranium maculatum (Fig. 141) is similar to 



G. carolinianum of the black 

 oak association. Its leaf is 

 not as finely cut, having 

 only five wedge-shaped lobes. 

 The blossom is larger, nearly 

 an inch across, and is light 

 purple. Canada violet (Fig. 

 142) has a branched, leafy 

 stem. The blossom is yellow 

 tinged with violet on the out- 

 side, white inside. The long- 

 spurred violet (Fig. 143) has 

 so conspicuously long a spur 

 that it is not to be mistaken 

 for any other in the Chicago 

 region. B oth these violets are 

 conspicuously present in the 

 climax forest. Rattlesnake 

 root, Prenanthes alba, is a composite with a stout and fairly high 

 stem, bearing leaves roughly triangular, though very variable in 

 form and lobing. The flowers are white, a dozen or so in a head 

 with many heads in a cluster (Fig. 144) . The summary of charac- 

 teristic plants is given in the tabulation at the close of this chapter. 

 The dune complex is by no means as simple as the foregoing 

 discussion would seem to indicate, for there are additional 

 physiographic changes that are constantly going on that inter- 

 fere with the orderly progression sketched above. Whenever a 



FIG. 137. Trunk of water beech, 

 Carpinus caroliniana. 



