Chapter I: Front Matter

YALE UNIVERSITY

MRS. HEPSA ELY SILLIMAN MEMORIAL LECTURES

PROBLEMS OF GENETICS

SILLIMAN MEMORIAL LECTURES
PUBLISHED BY YALE UNIVERSITY PRESS

ELECTRICITY AND MATTER. _By_ JOSEPH JOHN THOMSON,
D.SC., LL.D., PH.D., F.R.S., _Fellow of Trinity College,
Cambridge, Cavendish Professor of Experimental Physics, Cambridge_.
_Price $1.25 net; postage 10 cents extra._

THE INTEGRATIVE ACTION OF THE NERVOUS SYSTEM.
_By_ CHARLES S. SHERRINGTON,
D.SC., M.D., HON. LL.D., TOR., F.R.S.,
_Holt Professor of Physiology in the University of Liverpool_.
_Price $3.50 net; postage 25 cents extra._

RADIOACTIVE TRANSFORMATIONS. _By_ ERNEST RUTHERFORD,
D.SC., LL.D., F.R.S., _Macdonald Professor of Physics,
McGill University_.
_Price $3.50 net; postage 22 cents extra._

EXPERIMENTAL AND THEORETICAL APPLICATIONS OF
THERMODYNAMICS TO CHEMISTRY.
_By_ DR. WALTHER NERNST, _Professor and Director of the
Institute of Physical Chemistry in the University of Berlin_.
_Price $1.25 net; postage 10 cents extra._

THE PROBLEMS OF GENETICS. _By_ WILLIAM BATESON, M.A.,
F.R.S., _Director of the John Innes Horticultural Institution,
Merton Park, Surrey, England_.
_Price $4.00 net; postage 25 cents extra._

STELLAR MOTIONS.
WITH SPECIAL REFERENCE TO MOTIONS DETERMINED BY MEANS OF
THE SPECTROGRAPH. _By_ WILLIAM WALLACE CAMPBELL, SC.D., LL.D.,
_Director of the Lick Observatory, University of California_.
_Price $4.00 net; postage 30 cents extra._

THEORIES OF SOLUTIONS. _By_ SVANTE AUGUST ARRHENIUS,
PH.D., SC.D., M.D., _Director of the Physico-Chemical
Department of the Nobel Institute, Stockholm, Sweden_.
_Price $2.25 net; postage 15 cents extra._

IRRITABILITY.
A PHYSIOLOGICAL ANALYSIS OF THE GENERAL EFFECT OF
STIMULI IN LIVING SUBSTANCES.
_By_ MAX VERWORN,
_Professor at Bonn Physiological Institute_.
_Price $3.50 net; postage 20 cents extra._

THE EVOLUTION OF MODERN MEDICINE.
_By_ SIR WILLIAM OSLER, BART., M.D., LL.D., SC.D.,
_Regius Professor of Medicine, Oxford University_.
_Price $3.00 net; postage 40 cents extra._

PROBLEMS OF GENETICS

BY
WILLIAM BATESON, M.A., F.R.S.

DIRECTOR OF THE JOHN INNES HORTICULTURAL INSTITUTION,
HON. FELLOW OF ST. JOHN'S COLLEGE, CAMBRIDGE,
AND FORMERLY PROFESSOR OF BIOLOGY IN THE UNIVERSITY

_WITH ILLUSTRATIONS_

NEW HAVEN: YALE UNIVERSITY PRESS
LONDON: HUMPHREY MILFORD
OXFORD UNIVERSITY PRESS

MCMXIII

Copyright, 1913
By YALE UNIVERSITY

First printed August, 1913, 1000 copies

[** Transcriber's Note:
Underscores "_" before and after a word or phrase indicate ITALICS
in the original text.
Hyphenation was used inconsistently by the author and has been
left as in the original text. ]

THE SILLIMAN FOUNDATION

In the year 1883 a legacy of about eighty-five thousand dollars was left to the President and Fellows of Yale College in the city of New Haven, to be held in trust, as a gift from her children, in memory of their beloved and honored mother, Mrs. Hepsa Ely Silliman.

On this foundation Yale College was requested and directed to establish an annual course of lectures designed to illustrate the presence and providence, the wisdom and goodness of God, as manifested in the natural and moral world. These were to be designated as the Mrs. Hepsa Ely Silliman Memorial Lectures. It was the belief of the testator that any orderly presentation of the facts of nature or history contributed to the end of this foundation more effectively than any attempt to emphasize the elements of doctrine or of creed; and he therefore provided that lectures on dogmatic or polemical theology should be excluded from the scope of this foundation, and that the subjects should be selected rather from the domains of natural science and history, giving special prominence to astronomy, chemistry, geology, and anatomy.

It was further directed that each annual course should be made the basis of a volume to form part of a series constituting a memorial to Mrs. Silliman. The memorial fund came into the possession of the Corporation of Yale University in the year 1901; and the present volume constitutes the fifth of the series of memorial lectures.