II. — East and West Okoboji lakes near the strait joining tliem. 

 III. — The shores and border swamps around East and West Okoboji 

 lakes. 



lY. — The Gar lakes. 



T. — ^ The north end of East Okoboji lake. 

 VI. — -Kettle-holes and bogs between West Okoboji lake and the Little 

 Sioux river. 



VII. — Kettle-holes between East and West Okoboji lakes. 

 A'lII. — The smaller lakes northwest of Spirit lake, and the shores of 

 the latter. 



Localities I and II are comparatively deep water places with constant 

 beds of submersed or partly floating plants; columns III, VI and VII rep- 

 resent the shallower ponds and border swamps; columns IV and V are also 

 representative of rather deep water, but shallower than I; VIII represents 

 a combination of shallow waters and border swamps. 



2. — The letters in the first column indicate the usual habitat of the 

 species as follows: 



m. — Lakes and deeper ponds, 

 n. — ■ Borders of lakes and kettle-holes. 

 0. — Hillside bogs and seepj places. 



p. — ■ Higher, but moist grounds, moist borders of thickets, etc. 



3. — ■ The numbers in the columns indicate roughly the relative abundance 

 of the species as before. This varies very much with the seasons. During 

 wet seasons there is a relatively smaller number of border swamp species, and 

 an increase in the number of deeper water forms. The latter, however, are 

 less inclined to flower and fruit during such seasons. During dry seasons 

 the border plants cover larger areas, and there is a diminution in the nimi- 

 ber of deep water forms, but an increase in the relative number of flowers 

 and fruits. 





I 



II 



III 



IV 



V 



VI 



VII 



VIII 





Subkingdom III PTERIDOPHYTA 



Family Equisetacew 

 Equisetum hyemale robustum (A. 



Br.) A. A. Eaton n 

 Subkingdom IV SPEEMATOPHYTA 

 Subclass ^lOXOCOTYLEDOXE^ 

 Family TypJiacece 

 Typha latifolia L. n 



Family Sparga n mcecB 

 Sparganium americanmn androcla- 



dum (Eng.) F. & E. n 

 Sparganium eurycarpum Engelm. n 

 Sparganium simplex Huds. n 



Family Najaducece 

 Potamogeton americanus C. & S. m 

 Potamogeton amplifolius Tuck. m 

 Potamogeton dimorphus Eaf. m 



4 

 4 



4 



4 



3 



4 



3 

 4 





4 

 4 

 5 



3 



3 

 4 



3 



3 



4 

 4 





43 



