240 BOTANICAL GAZETTE [MARCH 
be applied with justice (if one excepts cytological research), will be a welcome 
wea to genetic literatur 
s present form, the a might very easily be divided into two books 
with sce titles that could be used independently. The one is a thorough 
introduction to statistical methods as they should be used in the service of 
iology; the other is a well balanced discussion of the present status of genetic 
conceptions. 
might be expected, it has been the general discussion of heredity that 
has received the bulk of the revision; the chapters on biometry were admirably 
done in the first edition, and the static nature of their substance was such that 
little change has been necessary. Scarcely a word has been altered in the first 
five chapters, though CHARLIER’s short method for determining the standard 
deviation has been added. In chapter 6 the discussion of mean error has been 
‘revised and a demonstration from the domain of plant physiology has been 
added. From this point to chapter 22, only chapters 12 and 13 are new, but 
the remainder of the book is entirely as written. 
In chapter 12 the more recent investigations concerning the possible effect 
of selection on pure lines are described, while in the next chapter the “misunder- 
standings” of certain authors who have opposed the theory of permanence of 
homozygous types are taken up and disposed of with very clear logic, though 
the style of the rejoinder is sometimes a little caustic. 
The last seven chapters of the book are so crowded with information that 
only a hint as to their contents can be given. They must be read by all who 
are interested in genetics. Sixty pages are given up to the influence of the 
factors of environment on variation and 160 pages to Mendelism in its various 
phases, including heterozygosis, inbreeding, sterility, coupling, and sex determi- 
nation. Mutations are considered rather concisely in the next to the last 
chapter, the author being rather of the opinion that the peculiar behavior of 
Oenothera Lamarckiana will ultimately be shown to be the result of segregation 
and recombination, as has been suggested recently by HERIBERT-NILSSON. 
The final chapter is a résumé, with observations on eugenics, race hygiene, and 
evolution. 
With reference to the position taken in his earlier Seg concerning the 
action of selection, the author remains as firm asarock. Hea ds further data 
of his own to support his position and shows very clearly hie the seemingly 
opposing conclusions of various investigators either are due to fallacious 
reasoning or are based upon material that is not easily divested of complications 
that confuse the main issue. To critics who deal only with generalities ~ 
makes the following reply that may well be taken to heart by those who d 
with evolution from an easy chair: 
5 
Man hat mich kurzsichtig genannt, in Bezug auf die Selektion. Ich gree 
dies mit Vergniigen; die Priimissen einer oft maszlosen spekulativen Fernsi 
waren ja gerade zu untersuchen und wiirden wertlos striate 
