626 
Haecker’s book by reason of its thorough- 
ness and scientific method of exposition will 
undoubtedly be to a large extent caviare to 
the general, but that by Castle will appeal to a 
much wider circle of readers as a clear and 
direct statement of the Mendelian principles 
and their application, couched in language as 
simple and untechnical as may be. Its title, 
compared with that selected by Haecker, is 
perhaps a little misleading, for the book is 
limited to an account of the Mendelian phe- 
nomena and their formal explanation. The 
cytological side of inheritance, so prominent 
in Haecker’s book, is barely considered; in- 
deed, it could hardly be expected in a book 
written for the general reading public. Tak- 
ing into account the limitations set by its 
purpose, the book is an excellent presentation 
of the Mendelian phenomena, based upon 
studies extending over some ten years, and 
while the general reader may in some cases 
find it difficult to follow the complexities of 
the phenomena, yet he will not fail to form 
an intelligent appreciation of the far-reach- 
ing significance of Mendelism. 
But it is not to the lay brother alone that 
the book will prove of interest. The expert 
will find much to interest him in its logical 
methods and in the résumé it presents of ex- 
tensive experience in experimental breeding, 
and in certain of the chapters, such, for in- 
stance, as those on Mendelism and Selection 
and on Heredity and Sex, he will be rewarded 
with no scanty supply of food for thought. 
Rigano’s work appeared in a French edi- 
tion as long ago as 1907 and an abstract of it 
by the present translator was published in 
The Monist in 1909. It is an attempt to for- 
mulate a new theory of heredity based on anal- 
ogy with certain electrical phenomena. The 
theory of centro-epigenesis, as it is named, as- 
sumes the existence in the germ plasma of 
certain specific potential elements, which send 
out in succession through the organism im- 
pulses which determine the various stages of 
its ontogeny, each specific impulse depositing 
in the nucleus of the cells to which it passes a 
definite substance, which, under similar con- 
SCIENCE 
[N.S. Vou. XXXV. No. 903 
ditions is again capable of producing the 
same specific impulse as that by which it was 
deposited. When ontogenesis is complete the 
organism is in a state of dynamic equilibrium 
so far as the epigenetic impulses from the 
germ plasm are concerned, but it is now re- 
ceiving functional stimuli, which in a similar 
manner produce specific impulses leading to 
the deposit of what may be a new kind of ma- 
terial. If the stimulus reaches the germ 
plasm new specific potential elements will be 
deposited in it and so the way is open for the 
inheritance of acquired characters. 
This is a bald statement of the essentials of 
the theory which is fully elaborated and com- 
pared with rival theories in the volume under 
consideration. Similarities with Semon’s 
theory of mnemes suggest themselves, and 
like this the theory can truthfully be said to be 
exceedingly suggestive. But if criticism may 
be made without entering into details, it 
would seem that centroepigenesis explains al- 
most too much, in furnishing possibilities for 
the inheritance of acquired characters far be- 
yond what reality demands. It is based on 
assumptions which at present we have no 
means of either proving or, what is much 
more difficult, disproving, assumptions drawn 
from what is not always a reliable source, 
namely from analogy. But right or wrong, it 
should serve to suggest lines along which the 
further investigation of the physiology and 
physics of the developing organism may ad- 
vantageously proceed. 
The translation, it should be stated, is well 
done and the translator is to be congratulated 
on having supplied English readers with an 
accurate and readable statement of the theory. 
J. P. McM. 
Nephritis, An Experimental and Critical 
Study of its Nature, Cause and the Princi- 
ples of its Relief. By Dr. Martin H. Fiscuer. 
(The 1911 Cartwright Prize Essay of the As- 
sociation of the Alumni of the College of 
Physicians and Surgeons, Medical Depart- 
ment of Columbia University, New York.) 
First edition, large 12mo. Pp. ix 203; 
