4 THE EGGS OF MAMMALS 



It is the earnest belief of the writer that these experi- 

 mental inquiries represent a small fraction of the work 

 that should and will be done. The enormous variety and 

 richness of mammalian material that is available and un- 

 tapped should provide an extraordinary temptation to ex- 

 ploitation now that a beginning has been made in the de- 

 velopment of technical facilities for the manipulation of 

 this material. I emphasize that only a beginning has been 

 made. This book is a beginning. 



