CONTENTS 
[All Rights resej'ved) 
I. A Piebald Family. By E. A. Cockayne, M.D., M.R.C.P. (With Plates XI— 
XVIII) 
II. Clypeal Markings of Queens, Drones and Workers of Vespa Vulgaris. By 
Oswald H. Latter, M.A. (With One Diagram in the text) 
III. Table of the Gaussian "Tail". Functions ; when the S'Tail" is larger than the 
Body. By Alice Lee, D.Sc. (With One Diagram in the text) . 
IV. Contribution to a Statistical Study of the Cruciferae. , Variation in the Flowers 
of Lepidium draba Linnseus. By James J. Simpson, M.A., D.Sc. (With 
Eleven Diagrams in the text) 
V. Nochmals iiber " The Elimination of Spurious Correlation due to Position in 
Time or Space." VoN 0. Anderson, Petrograd, EuBland .... 
VI. Statistical Notes on , the Influence of Education in Egypt. By M. Hosnt, 
M.A., B.Sc. . ' . . . . 
VII. Height and Weight of School Children in Glasgow. By Ethel M. Eldebton, 
■ Galton Fellow, University of Loudon. (With Plate XIX and Two Diagrams 
in the text) 288 
VIII. Numerical Illustrations of the Variate Difference Correlation Misthod. By 
Beatrice M. Cave and Karl Pearson, F.R.S. . . . . . 340 
IX. An Examination of some Recent Studies of the Inheritance Factor in Insanity. 
By David Heron, D.Sc. (With\ Fifteen Diagrams in the text) . . . 356 
X. On the Probable Error of the Bi- Serial Expression for the Correlation Coefficient. 
By.H. E. SoPBR, M.A. Biometrical Laboratory, University of London . . 384 
XI. On the Partial Correlation Ratio. Part I. Theoretical. By L. Isserlis, B.A. 391 
Miscellanea: ' 
(i) On Spurious Values of Intra-class Correlation Coefficients arising from Dis- 
orderly Differentiation within the Classes. By J. Arthur Harris, Ph.D. 
Carnegie Institution of Washington, U.S. A .412 
(ii) On an Extension of the Method of Correlation by Grades or Ranks. By 
Karl Pearson, F.R.S ■. . . . 416 
(iii) Correction of a Misstatement made by l^Ir Major Greenwood, Junior. K. P. 418 
(iv) Note on Reproductive Selection. By David Heron, D.Sc. .... 419 
PAGE 
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269 
280 
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