EXPLANATION OF MAP AND PLATES 



EXPLANATION OF MAP 



The squares bounded by full lines are sections, or square miles. The 

 quarter sections are marked by dotted lines (half section lines). The 

 shaded areas represent the original forest areas. 



EXPLANATION OF PLATE I 



Pig. 1 — • The Lookout, west of the Laboratory, a gravelly mound. Looking 

 south. Station 1 is marked. 



Fig. 2 — West side of Laboratory grounds. Native prairie on which Sta- 

 tion 2 was located. Looking north of west. Oct. 7, 1909. 



Fig. 3 — A tongue of native prairie extending into the woods along a ridge 

 just south of the Laboratory. Aug. 14, 1911. 



EXPLANATION OF PLATE II 



Fig. 1 — 'Looking north across Miller's Bay at the prairie hills beyond. 

 The Laboratory grounds are on the wooded point. Aug. 14, 1911. 



Fig. 2 — ■ The ' ' trough ' ' west of the Laboratory, looking northeast towards 

 the ridge shown in Fig. 1. The arrow shows the direction of the pre- 

 vailing southwest winds. Oct. 7, 1909. 



Fig. 3 — ' Elm Crest and woods, looking southeast at the abrupt northern 

 banks of the peninsula. Aug. 28, 1911. 



EXPLANATION OF PLATE III 



Fig. 1 — ■ Bur oak grove near Laboratory cottage. Station 3 was located 



near the lower left hand corner ; station 4 was back of the tree marked 



4. Looking southwest. Oct. 7, 1909. 

 Fig. 2 — ■ The Laboratory pier and steps. Station 5 was located north of the 



steps, and is marked 5. A little strip of prairie runs down to th:s 



station from the northwest. Oct. 7, 1909. 



EXPLANATION OF PLATE IV 



Leaf sections of prairie xerophytes. The letters in the several figures 

 represent the following structures : 

 a=Epidermis 

 b=Cutin 



c=Water storage cells 

 d=Trichomes 



The shaded cells are palisade cells. 



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