FOURTH ANNUAL MEETING. 21 



Oil Investigations in Illinois, by Raymond S. Blatchley. (^Illus- 

 trated.) 



Seasonal Succession in Old Forest Ponds, by W. C. Allee. 

 (Illustrated.) 



The Occurrence of the Rare Alga, Gloeotaenium, in Illinois, 

 by E. X. Transeau. 



Present Condition of the State ^^luseum of Natural History, 

 by Alja R. Crook. 



Demonstration of the Movement of the Water in Leaves, by 

 Aaron Hodgman Cole. (Illustrated.) 



The meeting adjourned at five o'clock, p. m. 



Evening. 



At eight o'clock, Professor S. A. Forbes called the meeting to 

 order in Mandel Hall, when the presidential address was delivered 

 by Prof. John M. Coulter. 



Following the presidential address, a social hour was spent in 

 Hutchinson Hall. 



SESSION OF SATURDAY. FEBRUARY 18. 



Morning. 



Mandel Hall, 9 :lo a. m. 



Symposium on Radioactivity. 



President Coulter in announcing the Symposium said that the 

 order of presentation would not be as shown on the printed pro- 

 gram, but would be such as to show the development of the situa- 

 tion. The addresses were accordingly delivered in the following 

 order : 



I. Some of the Physical Properties of Radium, by Prof. 

 Henry Crew of the Northwestern University. 



II. Radium from the Astronomical Point of \'iew, by Prof. 

 Edwin B. Frost of the Yerkes Observatory. 



III. Radiochemistr)-, by Prof. \\'illiam A. Noyes of the State 

 University of Illinois. 



IV. Radioactivity and Geological Phenomena, by Prof. 

 Thomas C. Chamberlin of the University of Chicago. 



