The authors dedicate this hoo\ to all 

 those straining in the pursuit of Truth 



•••(•-^©nQ^in^^)* 



The contents of this monoi^raph with the exception of 

 the General Bibliography, are reprinted from Biody- 

 naniica Xo. 33, 1938, No. 48, 1939 and Xo. 60, 1940. 



The honesty of the readers being beyond all suspicion, no author's 

 right is reserved in any country. 



