SEXUAL TENDENCIES IN MONKEYS 317 



and that their behavior, the types of which I could Have pre- 

 dicted before I entered the yard, was the expression of definite 

 organic properties. 



The essential points of the above discussion are these: (1) 

 The essential factors concerned in behavior phenomena are (a) 

 the action of physiological processes usually operating in con- 

 junction with environmental forces, in the production of (b) 

 hungers which impel the individual to manifest (c) activities, 

 the particular types or modes of which are to be ascribed to (d) 

 specific organic properties (reactive tendencies). (2) These 

 reactive tendencies are most conveniently classified with reference 

 to the individual hungers that bring them to expression. (3) 

 The term 'reactive tendency," according to my definition, is 

 meant to designate something more specific than an inclination 

 to direct activity toward one of a limited number of general ends, 

 and to include both the innate and the acquired features of an 

 individual's reactive mechanism. 



CONCLUSIONS 



At least two, and possibly three, different kinds of hunger, or 

 needs of individual satisfaction, normally impel the macaque 

 toward the manifestation of sexual behavior, viz., hunger for 

 sexual satisfaction, hunger for escape from danger and, possibly, 

 hunger for access to an enemy. 



Homosexual behavior is normally an expression of tendencies 

 which come to expression even when opportunities for hetero- 

 sexual intercourse are present. Sexually immature male mon- 

 keys appear to be normally impelled toward homosexual behavior 

 by sexual hunger. The fact that homosexual tendencies come 

 to less frequent expression in the mature than in the immature 

 male suggests the possibility that in their native habitat these 

 animals may wholly abandon homosexual behavior (except as a 

 defensive measure), on arriving at sexual maturity. 



Homosexual behavior is of relatively frequent occurrence in 

 the female when she is threatened by another female, but it is 

 rarely manifested in response to sexual hunger. 



Masturbation does not seem to occur under normal conditions. 



The macaque of both sexes is apt to display sexual excitement 

 in the presence of friendly or harmless non-primates. 



It is possible that the homosexual behavior of young males is 



