PREFACE 



THIS is the first time that the Physiology of the Organs 

 of Reproduction has been presented in a complete form, 

 and many who desire to obtain more precise knowledge 

 regarding the problems with which it deals, than is to be 

 found in text-books of Physiology, will welcome the 

 appearance of Dr. Marshall's book. The importance of 

 such knowledge to the community in general is now 

 becoming recognised, and the interest which the subject 

 awakens is no longer confined to members of the medical 

 profession and to breeders of animals. Especially will 

 the work furnish a much needed introduction to the 

 science of Eugenics, whilst the multiplicity of facts which 

 are set forth, and the manner in which questions of 

 difficulty are discussed, will have the effect at once of 

 satisfying and of stimulating inquiry in a most important, 

 if hitherto somewhat neglected, branch of Physiology. 



E. A. SCHAFER. 



UNIVEKSITY, EDINBURGH, 

 June 1910. 



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