Dr. Rodney H. True, Pro- 

 fessor of Botany, University 

 of Pennsylvania, Philadelphia. 

 Mineral nutrition of plants; 

 Toxic action of solutions; Tur- 

 gor; Growth and temperature. 



Dr. F. E. Lloyd, Profes- 

 sor of Botany, McGill Uni- 

 versity, Montreal, Canada. 

 Transpiration; Physiology 

 of stomata; Fluorescence. 



