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EXPLANATION OF PLATE II. 



(Mirror Lake views before the alterations made June, 1920). 



Fig. 1. The large pond; taken from the west end (near station 10) looking east- 

 ward; island in center; portion east of line crossing at about region of 

 stations 6 and 15, not visible. 



Fig. 2. The large pond; the east end, looking eastward from a point on north 

 shore midway between stations 7 and 15; stations 4 and 14 at left; 

 station 6 at right; connection with small pond under walk (white line) 

 to left of center. 



Fig. 3. The small pond; looking in northwest direction from southeast end; 

 station 3, darker area directly across at left of center; station 12 upper 

 right end of pond; duckweed (showing white) covering most of water. 

 August, 1920. 



Fig. 4. The small pond; looking across at east shore, north half; station 11 occupy- 

 ing most of foreground; station 13, the spring, open spot on shore to 

 left of center. August, 1920. 



