Volume II NOVEMBER, 1903 No. 4 



ON THE LAWS OF INHERITANCE IN MAN*. 



I. INHERITANCE (JF PHYSICAL CHARACTERS. , ipRARV 



By KARL PEARSON, F.R.S., assisted l)y ATJCE LEE, D.So. -tANVCA-^ 



University College, London. „ t^RDtN 



CONTENTS. 



Page 

 (i) Iiitroductory 3.57 



(ii) Material. Family Rocord Series 358 



(iii) Theory Applied 361 



(iv) Size and Variability of Cliaracters in two Ueuerations .... 370 



(v) Direct Assortative Mating in IMan 372 



(vi) Gross Assortative Mating in Man 375 



(vii) Direct Parental Inhei-itance 377 



(viii) Gross Parental Inheritance 383 



(ix) Direct Fraternal Correlation 387 



(x) Gross Fraternal Correlation 392 



(xi) General Gonclusions 393 



(xii) Appendix of Correlation Tables 397 



(i) Iiitroductory. 



Aboxjt eight years ago I determined to Supplement tlie data obtained by 

 Mr Francis Galton for bis work Natural Inheritance by a rather wider series of 

 measurements nn blood relations in man. Mr Galton had most generoiisly placed 

 his original data at my disposal and I bad used them as far as stature was 

 concerned in my memoir of ISDöf and in a Joint pajier witb Dr Lee in 1896|. 

 The eye-colour data of his Family Recoi'ds were not reduced§ until after the 

 discovery of a method for dealing witb characters not capable of e.xact quantitative 

 measurementll, and it is only recentl}- that tbe fidl sclienie of relationships back 

 to great-grandparents lias been coinpleted':. Tliere were about 200 families in 

 Mr Galton's records and only one measurable cbaracter, stature. The contlitions 



* I must gratefully acknowledge aid in tlie publication of tlic elaborate tables which aocompany Ulis 

 memoir from a Rrant made to my department iu the Uiüversity uf London by the Worshipful Company 

 of Drapers. 



t "Eegression, Heredity and Panmixia." Phil. Trans. Vol. 187, pp. 2.53 — 318. 



X "On TelcRony in Man." R. S. Proc. Vol. 60, p. 274 et. .sivy. 



§ "On the Inheritance of Eye Colour in Man." Phil. Trum. Vol. l'.ir», pp. 102—121. 



II "On the Correlation of Characters not qiiantitatively Measurable." Phil. TraHt. Vol. WH, 

 pp. 1—47. 



IT F. E. Lutz: "Note on the Influence of Change in Sex on the Intensity of Heredity." Binmetrika, 

 Vol. II. pp. 237—240. 



Bionietrika 11 46 



