Meeting of June 20, 1901, and List of Papers read. 367 



I. " On the Mathematical Theory of Errors of Judgment, with 

 Special Eeference to the Personal Equation." By Professor 

 Karl Pearson, F.R.S. 



II. " Mathematical Contributions to the Theory of Evolution. 

 X. — Supplement to a Memoir on Skew Variation." By 

 Professor Karl Pearson, F.R.S. 



III. " On the Application of Maxwell's Curves to Three-colour 



Work, with Especial Reference to the Nature of the Inks 

 to be employed, and to the Determination of the Suitable 

 Light-filters." By Dr. R. S. Clay. Communicated by 

 Sir W. Abney, K.C.B., F.R.S. 



IV. " The Nature and Origin of the Poison of Lotus Arabicus." By 



W. R. Dunstan, F.R.S., and T. A. Henry. 



V. "On the Structure and Affinities of Lipteris, with Notes on 

 the Geological History of the Dipteridinse." By A. C. 

 Seward, F.R.S., and Miss E. Dale. 



VI. " Further Observations on Nova Persei. No. 3." By Sir 

 Norman Lockyer, K.C.B., F.R.S. 



VII. "Total Eclipse of the Sun, May 28, 1900: Account of the 

 Observations made by the Solar Physics Observatory 

 Eclipse Expedition and the Officers and Men of H.M.S. 

 ' Theseus,' at Santa Pola, Spain." By Sir Norman Lockyer, 

 K.C.B., F.R.S. 



VIII. " The Mechanism of the Electric Arc " By Mrs. H. Ayrton. 

 Communicated by Professor Perry, F.R.S. 



IX. " The Yellow Colouring Matters accompanying Chlorophyll 



and their Spectroscopic Relations. Part 2." By C. A. 

 Schunck. Communicated by E. Schunck, F.R.S. 



X. " Magnetic Observations in Egypt, 1883-1901." By Captain 



H. G. Lyons. Communicated by Professor Rucker, F.R.S. 



XI. " A Determination of the Value of the Earth's Magnetic Field 



in International Units, and a Comparison of the Results 

 with the Value given by the Kew Observatory Standard 

 Instruments." By W. Watson, F.R.S. 



XII. "Virulence of Desiccated Tubercular Sputum." By H. 

 Swithinbank. Communicated by Sir H. Crichton 

 Browne, F.R.S. 



XIII. " The Effect of the Temperature of Liquid Air upon the 

 Vitality and Virulence of the Bacillus tuberculosis." By 

 H. Swithinbank. Communicated by Sir H. Crichton 

 Browne, F.R.S. 



