BIOMETRIKA 
A Journal for the Statistical Study of Biological Problems 
Founded by W. F. B. WELDON, FRANCIS GALTON and KARL PEARSON, edited, in 
consultation with FRANCIS GALTON and in collaboration with C. B. DAVENPORT, 
W. PALIN ELDERTON, W. R. MACDONELL, and RAYMOND PEARL, by KARL 
PEARSON. 
Contents of Yol. VI, Part IV, March 1909. (Price 10s net) 
I. Some Statistical Observations on Termites, mainly based on the work 
of the late G. D. Haviland. (With One Diagram in the text.) By 
Ernest Warren, D.Sc. 
II. Note on the Skin-Colour of the Crosses between Negro and White. (With 
Plate I.) By Karl Pearson, F.R.S. 
III. Ueber die Langenvariation der Coniferennadeln. (With 24 Diagrams in 
the text.) Yon A. Heyer. 
IY. Statistical Study of Anti-Typhoid Inoculation. (With One Diagram in the 
text.) By G. D. Maynard. 
V. A Biometric Study of Phagocytosis with Special Reference to the 
Opsonic Index. (With 16 Diagrams in the text.) By M. Greenwood, 
Junr. and J. D. C. White. 
YI. A Biometric Study of the Red Blood Corpuscles of the Common Tadpole 
(Rana temporaries), from the measurements of Ernest Warren, D.Sc. 
(With Two Diagrams in the text.) By Karl Pearson, E.R.S. 
VII. Data on Variation in the Comb of the Domestic Fowl. (With three pages 
of Diagrams in the text.) By R. and M. D. Pearl. 
Miscellanea. (i) Fecundity of Swine. (With Two Diagrams in the text.) By 
F. M. Surface. 
(ii) Frequency Constants of a Variable z =f(x 1 , x 2 ). By R. Pearl. 
(iii) The Correlation between a Variable and the Deviation 
of a Dependent Variable from its Probable Value. By 
J. Arthur Harris. 
Notices and Bibliography. 
The subscription price, payable in advance, is 80s. net per volume (post free); single numbers 
10s. net. Volumes I, II, III, IV, V and VI (1902—9) complete, 30s. net per volume. Bound in 
Buckram 34s. 6 d. net per volume. Index to Volumes I to V, 2s. net. Subscriptions may be sent 
to C. F. CLAY, Cambridge University Press, Fetter Lane, London, E.C., either direct or through 
any bookseller. 
TICKS 
A Monograph of the Ixodoidea 
By GEORGE H. F. NUTTALL, M.D., Ph.D, Sc.D., F.R.S., CECIL 
WARBURTON, M.A., F.Z.S., W. F. COOPER, B.A., F.Z.S., F.L.S., 
and L. E. ROBINSON, A.R.C.Sc. (London) 
Now Ready. PART I. THE ARGASIDAE. With 116 text 
Figures and 3 Plates. Royal 8vo. 5s. net 
This book will deal with the Classification, Structure and Biology of 
Ticks, the study of the group having occupied the authors for several years. 
Practically all that has been published on the subject has received adequate 
consideration. 
The book will be issued in about four parts, which will be complete in 
themselves but are designed to form a volume of about 500 pages when all 
the parts have been published. Each part will be issued in a stiff paper 
cover and will include a bibliography printed on one side of thin paper so 
that the references can be conveniently cut out and gummed on index cards. 
A complete bibliography, including all the publications cited in each part, 
will conclude the volume. 
CAMBRIDGE UNIVERSITY PRESS, FETTER LANE, LONDON 
C. F. CLAY, Manager 
