Proceedings at the Meetings 349 



February 17, 1919. 

 In the Comparative Anatomy Lecture Room. 



Mr C. T. E. Wilson, President, in the Chair. 

 The following Communications were made to the Society : 



1. Note on an experiment dealing with mutation in bacteria. By 



Dr DONCASTER. 



2. Electrical conductivity of bacterial emulsions. By Dr Shearer. 



3. The bionomics of Aphis grossulariae, Kalt., and Aphis viburni. 

 Shrank. By Miss M. D. Haviland. (Communicated by Mr H. H. 

 Brindley.) 



4. (1) The conversion of saw-dust into sugar. 

 (2) Bracken as a source of potash. 



By J. E. Purvis, M.A., Corpus Christi College. 



5. Terrestrial magnetic variations and their connection with solar 

 emissions which are absorbed in the earth's outer atmosphere. By 

 S. Chapman, M.A., Trinity College. 



6. The distribution of Electric Force between two electrodes, one 

 of which is covered with radioactive matter. By W. J. Harrison, M.A., 

 Clare College. 



May 19, 1919. 

 In the Cavendish Laboratory. 



Mr C. T. R. Wilson, President, in the Chatr. 



The following were elected Fellows of the Society : 

 E. V. Appleton, M.A., St John's College. 

 W. G. Palmer, M.A., St John's College. 

 S. P. Prasad, B.A., Trinity College. 



The following was elected an Associate : 



Mrs Agnes Arber. 

 The following Communications were made to the Society: 



1. (1) Use of Neon Lamps in Technical stroboscopic work. 



(2) The distribution of intensity along the positive ray parabolas 

 of atoms and molecules of Hydrogen and its possible 

 explanation. 

 By F. W. Aston, M.A., Trinity College. 



2. On a Micro-voltameter. By C. T. R. Wilson, M.A., Sidney 



Sussex College. 



3. The self-oscillations of a Thermionic Valve. By R. Whiddington, 

 M.A., St John's College. 



