The following species are represented: 

 Fig. 1 — Liatris scariosa Willd. 

 Fig. 2 — Verljeiia stricta Vent. 

 Fig. 3 — • Solidago rigida L. 

 Fig. 4 — Aster sericeus Vent. 



EXPLANATION OF PLATE V 



Fig. 1 — Twin Mounds, looking southeast. Mr. Boot's stations I, II, III 

 and IV, marked a, b, r, and d are represented on the southwest side. 

 Aug. 26, 1911. 



Fig. 2 — Bluffs on the west side of the Little Sioux river west and a little 

 south of Milford, looking west of south. Trees appear only on the 

 abrupt slopes. Aug., 1902. 



Fig. 3 — Bowldery beach. East side of West Okoboji lake, north of Ft. 

 Dodge Point. Aug., 1902. 



EXPLANATION OF PLATE VI 



Fig. 1 — Beach south of the Laboratory pier, looking north. Shows beach 

 zones of vegetation, mth bowldery beach in the background. The bare 

 portion is almost daily washed by the waves. Aug. 25, 1911. 



Fig. 2 — Sandy beach at the south end of Spirit lake, as it appeared at low 

 water in August, 1902 ; in more recent years covered with water. A 

 sandy prairie extends from this beach to the north end of East Okoboji 

 lake. Looking northeast. 



Fig. 3 — East shore of Center lake, looking north. Shows the disturbing 

 effect of ice-shove: a— ice; b=sand; c=ordinary undisturbed beach. 

 Dec. 8, 1911. 



EXPLANATION OF PLATE VII 



Fig. 1 — Marsh south of the hotel at Miller 's Bay, looking south, as it 

 appeared before the Beck canal was constructed. Aug. 2'8, 1911. 



Fig. 2 — A part of East Okoboji lake above the drawbridge at Spirit Lake, 

 as it appeared at low water in August, 1902. The plants are mostly 

 Sagittaria. In recent years mostly clear water. Looking northwest 

 from road. 



Fig. 3 — A part of the same lake just above the drawbridge, looking to- 

 .wards the wooded bluffs in Spirit Lake. Sagittaria in foreground and 

 mostly Scirpm fluvintilis along the shore. At low water in August, 

 1902. In recent years the foreground has been clear water. 



EXPLANATION OF PLATE VIII 



Fig. 1 — Kettleholes west of Lookout, near Laboratory, looking west. Oct. 

 7, 1909. 



Fig. 2 — Border of kettlehole east of the Inn, showing both aquatic and 



marsh border vegetation. August, 1902. 

 Fig. 3 — Aquatic garden in Miller 's Bay opposite the Laboratory, with the 



prairie hills shown in Plate II, fig. 1, in the background. Oct. 7, 1909. 



90 



