330 Prof. Karl Pearson. 



January 23, 1902. 

 Sir WILLIAM HUGGINS, K.C.B., D.C.L., President, in the Chair. 



Mr. Arthur John Evans, Captain Henry B. Jackson, and Professor 

 Charles J. Martin were admitted into the Society. 



A List of the Presents received was laid on the table, and thanks 

 ordered for them. 



The following Papers were read : 



I. " Mathematical Contributions to the Theory of Evolution. XI. 

 On the Influence of Natural Selection on the Variability and 

 Correlation of Organs." By Professor KARL PEARSON, F.R.S. 



II. "On the Correlation of Intellectual Ability with the Size and 

 Shape of the Head. (Preliminary Notice.)" By Professor 

 KARL PEARSON, F.R.S. 



III. " On the Mechanism of the so-called ' Peripheral Reflex Secretion ' 



of the Pancreas. (Preliminary Communication.)" By Dr. W. 

 M. BAYLISS and Dr. E. H. STARLING, F.R.S. 



IV. " A Short Description of the Culicidse of India, with Descriptions 



of New Species of Anopheles." By F. V. THEOBALD. Com- 

 municated by Professor E. RAY LANKESTER, F.R.S. 



V. " The Affinity of Tmesipteris with the Sphenophyllales." By 

 Professor A. P. W. THOMAS. Communicated by Professor 

 HOWES, F.R.S. 



VI. " On the Excretory Organs of Amphioxus." By E. S. GOODRICH. 

 Communicated by Professor E. RAY LANKESTER, F.R.S. 



" Mathematical Contributions to the Theory of Evolution. 

 XI. On the Influence of Natural Selection on the Varia- 

 bility and Correlation of Organs." By KARL PEARSON, F.R.S., 

 University College, London. Received December 20, 1901, 

 Read January 23, 1902. 



(Abstract.) 



The influence of directed natural or artificial selection on the 

 characters of a race is one which it is fundamental for the purposes of 

 evolution to appreciate quantitatively. I have already shown in an 



