PREFACE TO SECOND EDITION 



In preparing a new edition of "The Physiology of Eeproduction " 

 (the first edition having been for some time out of print) an attempt 

 has been made to bring the book up to date, and much new matter 

 has been added^ Dr. Cramer has enlarged and partly rewritten his 

 chapter on the "Biochemistry of the Sexual Organs," besides per- 

 forming a similar service in respect of Dr. Lochhead's chapter 

 on the " Changes in the Maternal Organism During Pregnancy," to 

 which many important additions have be^n made ; Dr. Lochhead, 

 unfortunately, owing to his professional duties at Gibraltar, having 

 been unable to revise his former contributions. The chapter on 

 "Foetal Nutrition and the Physiology of the Placenta," by the 

 latter author, has been reprinted practically as it originally stood, 

 excepting for certain slight additions, chiefly in the form of footnotes, 

 for which I am responsible. It is believed, however, that the chapter 

 is in no sense out of date, since the quantity of original work 

 done in this field during the last decade has been relatively small. 

 Dr. Shearer has added to the value of the chapter on " Fertilisation " 

 by including a description of the Oxidation Processes Occurring in 

 the Egg at and after Fertilisation, as well as an account of Child's 

 work on the Life Cycle; he has also given ane the benefit of his 

 wide knowledge of the literature in the revision of other parts of 

 the book. In addition to Dr. Cramer and Dr. Shearer, I wish also 

 especially to thank my colleague, Mr. John Hammond, for his valuable 

 and ready help in the preparation of this edition. Besides affording 

 me the advantage of his extensive knowledge and experience, he 

 has placed at my disposal his numerous notes relating to different 

 branches of Generative Physiology. 



I have pleasure in expressing my obligations to those authors, 

 editors, and publishers who (have permitted me to reproduce illustra- 

 tions from their respective works; in particular I must mention 

 Professor E. Steinach, of Vienna ; Dr. A. P6zard, of Paris ; and 

 Dr. H. D. Goodale, of Amherst, Mass., U.S.A. I am indebted also 



