IOWA ACADEMY OF SCIEXCE xi 
TABLE OF CONTENTS 
PAGE 
Letter of Transmittal ii 
Officers of the Academy iii 
Members of the Academy iv 
Table of Contents l-x 
Report of the Secretary 1 
Treasurer’s Report 3 
Report of Committee on Secretary’s Report 4 
Report of Membership Committee 5 
List of Members in Attendance G 
Program of the Iowa City Meeting 8 
V^Doctor Charles Edwin Bessey, L. H. Pammel 12 
Reverend David MacMillan Houghtelin, John L. Tilton 14 
The Inheritance of Syndactylism, Henry Albert 17 
The Theory of Binaural Beats — An Experimental Contribution, G. W. 
Stewart and Harold Stiles 18 
On the Lymphatic System of the Common Rat, Thestle T. Job 18 
V^Leaching of the Pleistocene Drifts of Eastern Iowa, ^Morris M. Lei^ton 19 
\/The Native and Cultivated Forest Trees and Shrubs of the Missouri 
River Basin, L. H. Pammel, G. B. MacDonald and H. B. Clark.... 23 
l/Ar'Cc>mparartive-Stud-y--of- the- Weeds of Central Iowa, Northern Minnesota 
and Wisconsin, L. H. Pammel. 57 
v^The Flora of the' Rainy River Region,. Harriette S. Kellogg 60 
/The Flo»a of the Ledges Region of Boone County, Iowa, Wm. W. Diehl.. 77 
Early Iowa Locality Records, B. Shimek 105 
/The Ecological Histology of Prairie Plants, Ella Shimek., 121 
y/A Hybrid Ragweed, Robert B. Wylie 127 
/Preliminary Notes on Nectar Production, L. A. Kenoyer 129 
/An Anomalous Hickory-Nut, Guy West Wilson. 133 
/An Exobasidium on Armillaria, Guy West Wilson.. 134 
/Pioneer Plants on a New Levee, Frank E. A. Thone 135 
V Flora of the East -Slope -of the Cascade Mountains in Crook County, 
Oregon, Morton E. Peck 143 
An Improved Heating Apparatus for Maintaining Constant Temperatures 
in Work with Polarimeters and Refractometers. J. N. Pearce 165 
A Convenient Standard Cell, Dieu Ung Huong and J. N. Pearce 169 
The 4-Nitro-5-Methyl-2-Sulphobenzoic Acid and some of Its Derivatives, 
Wm. J. Karslake and Perry A. Bond 175 
Some Well Known Building Materials, Nicholas Knight 213 
Acid Potassium and Acid Sodium Phthalates as Standards in Alkalimetry 
and Acidimetry, W. S. Hendrixson 217 
The First Coal-Washing Plant in Iowa, George F. Kay 225 
/The Extension of the Wisconsin Drift Southwest from Des Moines, John 
L. Tilton 229 
/The Age of the Terrace South of Des Moines, Iowa, John L. Tilton. ... 233 
/The Occurrence of Barite in the Lead and Zinc District of Iowa, Illinois 
and Wisconsin, W. D. Shipton 237 
/The Ste. Genevieve Formation and its Stratigraphic Relations in South- 
eastern Iowa, Stuart Weller and Francis M. Van Tuyl 241 
/Foundation of Exact Geologic Correlation, Charles Keyes 249 
'/Remarkable Prairie Synclinorium, Charles Keyes 268 
/contraposed Shore-Lines on Straits of Juan du Fuca, Charles Keyes.... 272 
