CONTENTS 
(All Bights reserved) 
PAGE 
I. i. Observations on the Occipital Bone in a Series of Egyptian Skulls with especial 
Reference to the Persistence of the Synchondrosis condylo-squamosa (Zaaijer, 
Synchondrosis intraoccipitalis posterior, BNA), By H. Dorothy Smith, B.Sc, 
Crewdson-Benington Student in Craniology. (With Plates I — VI) . . . 257 
II. A Study of Pygmy Crania, Based on Skulls found in Egypt. By H. Dorothy 
Smith, B.Sc, Crewdson-Benington Student in Craniology. (With Plates 
VII— XXIV) . . •_ . . . .262 
III. Notes on the Pigmentation of the Human Iris. By A. Rudolf Galloway, 
M.B., CM. (With Plate XXV in colours and One Diagram in text) . . 267 
IV. The Increase in the Number of Erythrocytes with Altitude. By Captain Hugh 
W. Acton, I.M.S. and Major W. F. Harvey, I.M.S. Pasteur Institute, Kasauli. 
(With Six Diagrams in text) 280 
V. A Study of the Negro Skull with Special Reference to the Congo and Gaboon 
Crania. By the late R. Crewdson-Benington, M.D., prepared for press by 
Karl Pearson, F.R.S. (With Plate XXVI, and Four Diagrams in text and 
Five folding tables of measurements) 292 
Appendix : Tables to facilitate calculation of the Rhinal Indices. By Julia Bell, M.A. . 338 
VI. On the Relation of Stature and Weight to Pigmentation. By Ethel M/Elderton, 
Galton Eugenics Laboratory 340 
VII. Pigmentation in relation to Selection and to Anthropometric Characters. By 
A. M. Carr Saunders, M.A. (With Three Diagrams in text) . . . 354 
VIII. Supplementary Tables for finding the Correlation Coefficient from Tetrachoric 
Groupings. By P. F. Everitt, B.Sc. . . . . . . . . 385 
IX. Note on the Extent to which the Distribution of Cases of Disease in Houses 
is determined by the Laws of Chance. • By J. McD. Troup, M.B., and 
G. D. Maynard, F.R.C.S.E 396 
X. On the Appearance of Multiple Cases of Disease in the same House. By Karl 
Pearson, F.R.S. . . . . . 404 
XI. Growth, Variability and Correlation in Young Trout. By J. W. Jenkinson, 
M.A., D.Sc. . . . . . . . . . ' * 444 
Miscellanea : 
(i) A Simplified Method of calculating Frequencies of Occurrence, from a large 
number of Unequal Probabilities. By Captain G. McKendrick, I.M.S. 
Pasteur Institute, Coonoor 413 
(ii) The Application of the Correlation Coefficient to Mendelian Distributions. 
By E. C. Snow, M.A 420 
(iii) A Mendelian View of Racial Heredity. By H. J. ( Laski. (With Three 
Diagrams in text) 424 
(iv) On "Cancer Houses," from the Data of Dr Law Wells. By Karl 
Pearson, F.R.S. 430 
(v) Hybridisation of Canaries. By A. Rudolf Gaxloway, M.B., M.A. . . 435 
(vi) An Attempt to ascertain the Prevalence of Syphilis in a large Urban Popu- 
lation. By W. f V. E. . . . . . . : .437 
(vii) On the General Theory of the Influence of Selection on Correlation and 
Variation. By Karl Pearson, F.R.S 437 
(viii) On a Fallacious Proof of Sheppard's Correction. By K. P. . . . . 443 
Biometric Workers and Statistical Reviewers. A Letter, from E. C. Snow, M.A. 456 
The publication of a paper in Biometrika marks that in the Editor's opinion it, contains either in 
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