Potentilla Nicolletii (Wats.) Sheld. Ill 

 Lycopus americanus Muhl. VII 

 Gerardia tenuifolia Vahl. IV 

 Boltonia asteroides (L.) L'Her. Ill, IV 



Several aquatic and swamp species were added to the list. 

 They should be inserted in the hydrophytic list, pp. 43-49 : 

 Carex lanuginosa MicM. n, VI, 1; VII, 1. 

 Eriophorum angustifolium Roth n, VI, 2 ; VII, 3. 

 Lemna minor L. m, III, 1. 

 Cypripedium candidum Muhl. n, VI, 4. 

 Hippuris vulgaris L. n, IV, 4. 

 Gentiana crinita Froel. n, VI, 2. 

 Gentiana Andrewsvi Gris. n, VI, 4. 

 Bidens laevis (L.) BSP, n, IV, 4. 



Aquatic plants flourished, and some of the species, notably 

 TJtricularia vulgaris var, americana, occurred in unusual num- 

 bers. On the other hand ValUsneria, Elodea, some of the species 

 of Potamogeton, etc., were not much in evidence, the high level 

 of the water in the lake keeping them submerged. Bidens Beckii, 

 usually abiuidant and with many of its heads raised above the 

 water, was less abundant and remained entirely submersed, 

 though flowering abundantly, excepting in the canal between 

 Miller's Bay and Emerson's Bay, where occasional heads ap- 

 peared above vfater. Wolffia columbinana Karst., added to the 

 aquatic list, was very abundant in ponds connecting with the 

 west side of West Okoboji lake. Numerous flowering specimens 

 were' collected in August. On the whole, the deeper water 

 species of flowering plants suffered because of the higher level 

 of water, while the marsh and low ground species were favored. 



The two successive favorable seasons also produced their effect 

 upon the flora of the prairies. The usual yellowish or brown 

 color which marks the prairie slopes during the latter part of 

 August was missing, for the vegetation remained fresh even 

 through the hot days of July and August. Stipa spartea was so 

 abundant on the knolls and upland prairies that it prevented 

 fieldwork on the prairies for a week on account of the extremely 

 abundant fruit. Several species which belong in the Prairie list 

 were added during 1916, and they should be inserted in the 

 earlier list in the columns indicated by number. Those marked 

 '4" in that list are introduced species: 



Humulus lupulu^ L. d, VIII, 3. 



Medicago Lupulina L. i, VII, 4. 



4 



