•410 
IOWA ACADEMY OP SCIENCE Vol. XXIV, 1917 
PLANT LIST— Continued 
Sta. I 
Sta. II 
Sta. Ill 
Sta. IV 
Aster paniculatus var. lanatus F'er- 
nald 
Bidens frondosa L. 
'+ 
Bidens laevis (L.) BSP 
+ 
Cirsium iowense (Pammel) Fernald 
+ 
+ 
Eupatorium perfoliatum L 
+ 
Erigeron canadensis L 
+ 
+ 
Erigeron ramosus (Walt.) BSP 
+ 
Cirsium canescens Nutt 
+ 
THE FLORA. 
I ( SECOND ARRANGEMENT OF LIST.) 
The sharp transition in floras from one station to another is 
shown by the following list of the same plants as given in the 
preceding list, but arranged by. stations instead of in the order 
of plant relationship. The 4- indicates the presence of the plant 
at any station, and the continuous line of + ? s gives a regular 
curve of transition from Station I to Station IV. 
Station I is river bottom, Station II is lower forest level of 
north face of bluff, Station III is upper forest level of north 
face of bluff, Station IV is bare prairie of hill top and south- 
west slope of hill. 
Sta. I 
Sta. II 
Sta. Ill 
Sta, IV 
Acer Negundo L 
+ 
+ 
+ 
Acer saccharinum L 
+ 
Acnida tuberculata . Moq 
+ 
Agastache nepetoides (L.) Ktz 
+ 
+ 
Alnus sp 
+ 
Amaranthus retroflexus L 
+ 
Arctium minus Bernh 
+ 
+ 
+ 
Aster lateriflorus var. thyrsoideus (Gr.) 
Sheld 
+ 
+ 
Aster paniculatus var. lanatus Fernald 
+ 
Bidens frondosa L. . 
+ 
Bidens laevis (L.) BSP 
+ 
Campanula americana L 
+ 
+ 
Chenopodium hybridum L 
+ 
+ 
Circaea lutetiana L 
+ 
Cirsium canescens Nutt 
+ 
Cirsium iowense (Pammel) Fernald 
+ • 
+ 
Echinocystis lobata (Michx.) T. & G 
+ 
Eupatorium perfoliatum L 
T- 
Euphorbia marginata Pursh 
+ 
+ 
Euphorbia petaloidea Engelm 
+ 
Euphorbia Preslii Guss 
+ 
