490 Proceedings at the Meetings 



7. Animal oecology in deserts. By P. A. Buxton, M.A., Trinity 

 College. 



8. The Biology of the Crown Grail Fungus of Lucerne. By J. Line, 

 M.A., Emmanuel College. 



May 2, 1921. 

 In the Cavendish Laboratory. 



Professor Seward, President, in the Chair. 



The following Communications were made to the Society : 



1. On active molecules in physical and chemical reactions. By 

 E. K. Rideal, M.A., Trinity Hall. 



2. {a) An experiment which favours the resonance theory of hearing. 

 (6) A criticism of Wrightson's theory of hearing. 



(c) A method of projecting interference bands. 

 {d) A method of projecting absorption spectra, 

 (e) The shift of absorption bands with change of temperature. 

 By H. Hartridge, M.D., King's College. 



3. The cooling of a solid sphere with a concentric core of a different 

 material. By H. S. Carslaw, Sc.D., Emmanuel College. 



4. An alignment chart for thermodynamical problems. By C. R. G. 

 CoSENS, B.A. (Communicated by Professor Ingiis.) 



5. Symbolical methods in the theory of Conduction of Heat. By 

 T. J. I'a. Bromwich, Sc.D., St John's College. 



6. On a property of focal conies and of bicircular quartics. By 

 C. V. Hanumanta-Rao, M.A., Trinity College. (Communicated by 

 Professor H. F. Baker.) 



May 16, 1921. 

 In the Comparative Anatomy Lecture Room. 



Professor Seward, President, in the Chair. 



The following was elected an Associate of the Society : 

 A. Pratt, Magdalene College. 



The following Communications were made to the Society : 



1. The soaring flight of Dragon-flies. By E. H. Hankin, Sc.D., 



St John's College. 



2. An unusual type of secondarv male characters in the Diptera. 

 By C. G. Lamb, M.A., Clare College. " 



3. A note on the mouth-parts of certain Decapod Crustaceans By 

 L. A. BoRRADAiLE, M.A., Selwyn College. 



