236 APPENDIX 



helped us likewise. The text has been gone over 

 in parts by Dr. F. N. Duncan, Mr. Alexander 

 Weinstein, Mr. E. Altenburg and Mr. D. B. Young; 

 we wish to express our appreciation for the help 

 they have given. Four well-known geneticists have 

 looked through the last three chapters and have 

 made valuable suggestions. They are not named 

 here lest we appear to commit them to opinions with 

 which they may not agree in all details, but on the 

 whole we know that they do in general agree with 

 the interpretation of the factorial hypothesis that 

 we have followed. We express to them individually 

 our appreciation of their advice and criticism. 



