36 THE NA TURE-STUD Y RE VIE W [6:2-Feb., uuo 



lower animals in their life history and life processes, discuss 

 freely, among- other things, reproduction in these lower forms, 

 beginning with the protozoa and passing up step by step to the 

 higher animals, until finally reproduction among the mammals 

 is freely discussed as to its biological and physiological relations. 



That these teachers ever carry the subject so far as to dis- 

 cuss with their pupils problems of human sex life, I doubt. 

 However, the student of biology who has followed the subject 

 as far as indicated above, would readily infer a very large part of 

 the application of the general principles to the human subject. 



An attempt to present even the biology of reproduction to 

 a mixed audience of young people in a single address would be 

 in a high degree unwise. As a rule, then, to which there can 

 be few and rare exceptions, the problems of sex should be dis- 

 cussed in homogeneous audiences where one sex and age is 

 segregated from another. 



3— The Matter to be Presented 



Having divided the hearers into homogeneous groups, 

 what shall be presented to each group? Manifestly, the parents 

 are interested in the far broader field and capable of under- 

 standing a far greater range of facts than are the children. 



A group of boys of ten to fourteen should be told only 

 those things that boys of that age need to know; for example, 

 questions regarding reproduction: What goes on in an egg 

 during incubation? What has the rooster to do in the process? 

 Where do babies come from? What are general steps of their 

 development within the body of the mother? Why do they 

 begin to develop within the body of the mother? What has the 

 father to do with this process? Then there are questions of 

 physical development in the boy. To many boys these ques- 

 tions do not occur, but they should have them brought to their 

 attention. They should be told how every boy passes through 

 stages in his development in which he assumes gradually the 

 stature, the mental qualities and the functions of manhood. 

 It should be made clear to the boys that, to a large degree, 

 they have it in their hands whether this development shall be 

 a normal one, leading to stalwart virile manhood, or an abnormal 

 one absorbed by vicious habits. 



A group of older boys, fourteen to seventeen, may be given 

 another chapter in the story of reproduction. Boys of that age 



