116 
IOWA ACADEMY OF SCIENCE Voi,. XXVII, 1920 
phyllum peltatum, Hepatica acutiloha, Cystopteris fragilis, C. hulhifera. 
Camptosorus rhizophyllus, Asplenium Filix-femina, Pellea atropurpurea, 
Botrychium virginianum, Adiantum pedatum, Struthiopteris Germanica, 
Hydrastis canadensis, Actaea ruhra, Panax quinquefolium, Arabis race- 
mosa, Cypripedium pubescens, Caulophyllum thalictr aides, Rhus typhina. 
Clematis virginiana, Hamamelis virginiana, Physocarpus opulif alius, Sicyas 
angulatus, Palyninia canadensis, Impatiens pallida, Impatiens biflara. 
FLORA OF THE BLUFFS ON THE EAST SHORE OF MISSISSIP- 
PI RIVER NEAR PRAIRIE du CHIEN 
Quercus velutina, Papulus tremulaides, Betula papyrifera, Carya alba, 
Ulmus fulva, Rhus glabra, Rhus taxicadendran, Carylus americana, Vitis 
vulpina, Andrapagan furcatus, A. scaparius, Sarghastrum nutans, Spara- 
balus langif alius, Bautelaua curtipendula, B. hirsuta, Panicum scribner- 
ianum, Blymus rabustus, Muhlenbergia mexicana. 
PLANTS FREQUENTED BY HONEY BEES 
( Figures 
Compositas 
Aster salicifolius 
Grindelia squarrosa 
Helenium autumnale 
Polymnia canadensis 
Solidago canadensis 
Solidago missouriensis 
Solidago rigida 
Cucurbitaceae 
Sicyos angulata 
Labiatae 
Lycopus americana 
20 , 21 , 22 ) 
Mentha canadensis 
Nepeta cataria 
Leguminosae 
Apios tuberosa 
Polygonaceae 
Polygonum muhlenbergii 
Polygonum pennsylvanicum 
Ranunculaceae 
Clematis virginiana 
Scrophulariaceae 
Scrophularia marilandica 
No accurate data were taken on the distribution of Bowers 
per unit area. Plants with loose paniculate inflorescence such as 
Clematis and Sicyos or racemes such as those of Polygonum or the 
looser clusters of Apios involved much more of the time as well as 
the energy of the bee in covering space and making visits. The 
Compositae such as Golden Rod or Helenium produce obviously 
manyfold more flowers per unit area than the plants of the former 
groups. All of the plants listed have the colonial habit with the ex- 
ception of the rare Apios or Scrophularia. The Compositae along 
the streams or the shaded west river banks were much more sparse- 
ly distributed than on the islands (Fig. 23) or on the flood plains 
(Fig. 24) where acres of white Aster, Cardinal, Lobelia or Golden 
Helenium emblazoned the earth. The Asters and Heleniums of 
the flood plain and islands were giants compared with the dwarfs 
of the meadow country inland. 
