{All Rights reserved) 
BIOMETRIKA. Vol. XII, Parts III amd IV 
CONTENTS 
PAGE 
I. On the Mathematical Expectation of the Moments of Frequency Dis- 
tributions. By Professor Al. A. TcHOUPEOFF of Petrograd. Part II 185 
ir. Atr Explanation of Deviations from Poisson's Law in Practice. By 
Student ...... 211 
III. The Criterion of Goodness of Pit of Psychophysical Curves. By 
Godfrey H. Thomson, D.Sc. (One Diagram in text) . . . 216 
IV. On Corrections for the Moment-Coefficients of Limited Range Frequency 
Distributions when there are finite or infinite Ordinates and any 
Slopes at the Terminals of the Range.' By Eleanor Pairman and 
Karl Pearson, F.R.S. (One Diagram in text) .... 231 
V. Peccaviniiis ! Editorial 259 
VI. Quadrature Coefficients for Sheppard's Formula (c). Calculated by 
P. F. EvERiTT . . 282 
VII. On generalise Tchebycheff Theorems in the Mathematical Theory of 
Statistics. By Karl Pearson, F.R.S. . . • . . . 284 
VJII. Charles B. Goring, 1870 — 1919. Obituary Notice and Appreciations. 
(Plate I) . 297 
IX. On the Nest and Eggs of the Common Tern {S. fluviatilis). A Second 
Cooperative Study. (Plates II — VI and One Diagram in text) . 308 
X. On the Degree of Perfection of Hierarchical Order among Correlation 
Coefficients. By Godfrey H. Thomson, D.Sc. (Two Diagrams 
in text) . 355 
Miscellanea : 
(i) Inheritance of Psychical Characters. By Karl Pearson, F.R.S. 
(Plate VII) 367 
(ii) Variation and Distribution of Leaves in Sassafras. By N. M. Griee . 372 
(iii) Life-History Albums, By Ethel M. Elderton ..... 373 
(iv) The Check to the Fall in the Phthisis Death-rate since the Discovery of 
the Tubercle Bacillus and the Adoption of Modern Treatment. 
By Karl Pearson, F.R.S. (Plate VIII and One Diagram in text) . 374 
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