2 INTERNAL SECRETIONS 



view. In drawing a definite distinction between primary 

 and secondary sexual characters one might intend to express 

 the idea of an ontogenetic dependence of the second upon the 

 first. One might imply that the formation and full develop- 

 ment of the morphological and physiological sexual characters 

 — and under the latter we have to reckon also the ps\^chical 

 differences between the two sexes — depend upon the sexual 

 gland or the primary sexual characters. One would then 

 understand that the terms in question are not used merely 

 as more or less conventional definitions necessary for mutual 

 understanding, but that they in reality involve a kind of 

 explanation of the ontogenetic origin of certain characters. 

 There is implied in this distinction of primary and secondary 

 characters something of the nature of a genetic system of 

 sexual differences. 



Certain questions should be answered before one is in a 

 position to group the sexual characters in such a genetic 

 system. These questions may now be formulated. 



(i) Is it possible to show that certain sexual characters are 

 in a genetic dependence upon the sexual glands, i.e., to show 

 that the ontogenetic development of these sexual characters 

 is influenced by the sexual glands, and that the further per- 

 sistence of these characters depends on the presence of the 

 sexual glands ? 



(2) Does the formative and preserving influence of the 

 sexual glands concern all the sexual characters, or, in other 

 words, are all or only some of the sexual characters in a genetic 

 dependence upon the sexual glands ? In the latter case only a 

 certain number of the sexual characters could be described 

 as genetically secondary in comparison with the sexual glands. 



(3) If it be shown that only certain sexual characters are in 

 a genetic dependence upon the sexual glands, there arises the 

 question whether the formative and preserving influence of the 

 sexual glands relates only to characters necessary for the 

 performance of the sexual function, or whether the influence 

 of the sexual glands concerns also other sexual characters 

 which are in a more distant relation to the sexual function, or 

 are in no relation to them at all. 



(4) How far does this genetic dependence on the sexual 

 glands go, i.e., is a development of sexual characters for the 

 full differentiation of which the sexual glands are necessary. 



