CONTENTS- 
{All Eights reserved) 
PAGE 
I. Walter Frank Raphael Weldon. 1860—1906. (With two Portraits 
and three Plates) . . . . . . . .. . . 1 
II, Variation in Ghilomonas under Favourable and Unfavourable Con- 
ditions. (With seven Figures in the Text.) By Raymond Pearl .63 
III. The Non-Inheritance of Sex in Man. By Fredebick Adams 
Woods, M.D. . . . . 73 
IV. On the Inheritance of the Sex-Ratio. By David Heron, M.A. . 79 
V. A Second Study of the English Skull, with special Reference to the 
Moorfields Crania. (With superimposed Maps and 12 Plates of 
Crania, and four folding Tables.) By W. R. Macdonell . . 86 
VI. On the Relationship of Intelligence to Size and Shape of Head, and 
to other Physical and Mental Characters. (With nine Figures 
in the Text.) By Karl Pearson, F.R.S. . . . . .105 
VII. On the Relation between the Symmetry of the Egg and the Symmetry 
of the Embryo in the Frog (Rana Temporaria). (With twelve 
Figures in the Text.) By J. W. Jenkinson, D.Sc^ . . . 147 
Miscellanea, (i) Skew Frequency Curves. A Rejoinder to Professor 
Kapteyn. By Karl Pearson, F.R.S. . , . 168 
(ii) On the Curves which are most suitable for describing 
the Frequency of Random Samples of a Population. 
By Karl Pearson, F.R.S. . . . . . . 172 
(iii) On certain Points connected with scale Order in the 
Case of Correlation of two characters, which for some 
arratigeraent give a Linear Regression Line. By 
Karl Pearson^ F.R.S .176 
(iv) On "the Classification .of Frequency Ratios. (With one 
Figure in the Text.) By D. M. Y. Sommerville, D.Sc. 179 
(v) Note on the Significant or Non-Significant Character of 
a Sub-sample drawn from a Sample. By 'Karl 
' - Pearson, F.R.S. . 181 
(vi) Professor Ziegler and Galton's Law of Ancestral Inherit- 
ance. By Edgar Schuster . . . . . 184 
(vii) Variazione ed Omotiposi helle infioresceuze di Gichorium 
' Intyhus L. (With two Figures in the Text.) By 
Dr Fernando de Helguero ..... 184 
(viii) The Calculation of the Probable Errors of Certain Con- 
stants of the Normal Curve. By Raymo^jd Pearl . 190 
(ix) On the Probable Error of the Coefiicient of Mean Square 
Contingency. By J. Blakeman, M.Sc. and Karl 
Pearson, F.US. . . . . . . . .191 
(x) On a Coefficient of Class Heterogeneity or Divergence. 
By Karl Pearson, F.R.S. ., ; . . , .198 
(xi) Inheritance in the Female Line of Size of Litter in Poland 
China Sows. By G. M. Rommel and E. F. Phillips . 203 
Notices and Bibliography 206 
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