An experience of forty years in my professional career has afforded me thousands of opportunities for sympathizing with young men, and young women too, who had unconsciously sunk into these very evils merely for want of an able writer to place this whole subject truthfully and squarely before them, or for some wise friend to perform the same kind office verbally. The perusal of a work by Wm. Acton, M. R. C. S., of London, on "The Functions and Disorders of the Reproductive Organs in Childhood, Youth, Adult Age, and Advanced Life," has, by his purity of sentiments, which have ever been identical with my own, both inspired and emboldened me to write a work of similar import. But his is for the profession while mine is for the profession and the laity, of both sexes and of any age. May its perusal inspire the readers with a higher appreciation of the matters herein treated, and with a greater effort to reformatory measures everywhere. Whenever I advise the consulting of a "judicious" (a term I use many times) physician, I mean one fully and practically qualified, both by inherent qualities and education, for the fullest confidence of his patients. I am indebted to my son, Joseph C. Guernsey, M. D., for assistance in editing and carrying this work through the press. Henry N. Guernsey, M. D., 1423 Chestnut St., Philad'a. June, 1882. CONTENTS. CHAPTER I. Introductory, 13 CHAPTER II. The Infant, 24 CHAPTER III. Childhood, 27 CHAPTER IV. Adolescence of the Male, 42 CHAPTER V. Adolescence of the Female, 68 CHAPTER VI. Marriage.--The Husband, 84 CHAPTER VII. The Wife, 90 CHAPTER VIII. Husband and Wife, 100 CHAPTER IX. To the Unfortunate, 110 CHAPTER X. Origin of the Sex, 117 CHAPTER I. Introductory.