CONTENTS 
[All Rights reserved) 
PAGE 
I. W. R. Macdonell, Born October 16, 1852 ; Died May 15, 1916 (Notice 
with Portrait) . 281 
II. Further Supplementary Tables for Determining High Correlations from 
Tetrachoric Groupings. By Alice Lee, D.Sc. . . , . . 284 
III. On the Probable Error of Biserial rj. By Karl Pearson, F.R.S. (With 
One Figure in the Text) . . . . . . . . .292 
IV. A Preliminary Report on some Breeding Experiments with Foxgloves. By 
Ernest Warren, D.Sc 303 
V. On the Distribution of the Correlation Coefficient in Small Samples. 
Appendix II to the Papers of "Student" and R. A. Fisher. A Coopera- 
tive Study by H. B. Soper, A. W. Young, B. M. Cave, A. Lee and 
K. Pearson. (With Plates XXIV— XXVIII and Two Figures in the 
Text) 328 
'Miscellanea : 
(i) Tables for estimating the Probability that the Mean of a unique Sample of 
Observations lies between — oo and any given Distance of the Mean of 
the Population from which the Sample is drawn. By "Student" . 414 
(ii) On the Representation of Statistical Data. By L. Isserlis, D.Sc. (With 
Three Figures in the Text) . 418 
(iii) Relation of the Mode, Median and Mean in Frequency Curves. By Arthur 
T. DooDSON, M.Sc. . . .425 
(iv) The Probable Error of a Mendelian Class Frequency. By Karl 
Pearson, F.R.S. . .429 
Notice to Subscribers 
The great delay in the issue of this part of Biometrika has been due to a variety of causes which 
it is desirable to indicate here. In the first place the Editor and the whole of his StafE have been 
engaged on war work, which since July 1916 has become so incessant and engrossing that all research 
investigations have had to be placed on one side. In the next place three members of the Staff, who were 
originally engaged on the very heavy calculations of the memoir in this part dealing with the correlation 
coe£Bcient in small samples have left to undertake special work in the present crisis. And lastly the 
war depletion of the staff of the Cambridge University Press has inevitably delayed the setting up of 
a part involving such a great mass of numerical matter. 
The publication of a paper in Biometrika marks that in the Editor's opinion it contains either in 
method or material something of interest to biometricians. But the Editor desires it to be 4istinctly 
understood that such publication does not mark assent to the arguments used or to the conclusions 
drawn in the paper. 
Biometrika appears about four times a year. A volume containing about 500 pages, with plates and 
tables, is issued annually. 
Papers for publication and books and offprints for notice should be sent to Professor Kaei, Peaeson, 
University College, London. It is a condition of publication in Biometrika that the paper shall not 
already have bern issued elsewhere, and will not be reprinted- without leave of the Editor. It is 
very desirable that a copy of all measurements made, not necessarily for publication, should accom- 
pany each manuscript. In all cases the papers themselves should contain not only the calculated 
constants, but the distributions from which they 'have been deduced. Diagrams and drawings should be 
sent in a state suitable for direct photographic reproduction, and if on decimal paper it should be blue 
ruled, and the lettering only pencilled. ^ 
Papers will be accepted in French, Italian or German. In the last case the manuscript should be 
in Boman not German characters. Bussian contributors may use Bnssian bat their papers will be 
translated into English before publication. 
Contributors receive 25 copies of their papers free. Fifty additional copies may be had on 
payment of 7/- per sheet of eight pages, or part of a sheet' of eight pages, with an extra charge for 
Plates ; these •should be ordered when the final proof is returned. 
The subscription price, payable in advance, is 30s. net; per volume (post free) ; single numbers 
10s. net. Volumes I — XI (1902 — 17) complete, 30«.' net per volume. Bound in Buckram 34/6 net per 
volume. Index to Volumes I to V, 2s. net. Subscriptions may be sent to C. F. Clay, Cambridge Uni- 
versity Press, Fetter Lane, London, E.G. 4, either direct or through any bookseller, and communications 
respecting advertisements should also be addressed to C. F. Clay. 
Till further notice, new subscribers to Biometrika may obtain Vols. I — XI together tor £13 net — or 
bound in Buckram for £14 net. 
The Cambridge University Press has appointed the University of Chicago Press Agents for the sale 
of Biometrika in the United States of America, and has authorised them to charge the following prices : — 
$7.50 net per volume ; single parts $2. 50 net each. 
cambridgk: printed by j. b. peace, m.a., at the university press. 
