INHERITANCE OF SEX AND RELATED PHENOMENA 217 



have gone about three-fourths of the way toward the assumption of 

 the entire set of female characters. 



Goldschmidt ascribes these results to differences in potency of the sex- 

 factors. The European gypsy moth was found in all races to possess sex- 

 factors of low potency, whereas in the Japanese races the potency was 

 in general higher, but ranged from the lowest to the highest condition. 

 Thus males of a moderately strong Japanese race mated to females of a 

 Japanese race of slightly less potency give in F\ very low-grade female 

 intersexes. When mated to a somewhat less potent Japanese race a 

 higher grade of female intersexualism results, and when mated to the 

 weakest European race nothing but high-grade female intersexes are 

 produced. The highest grade of female intersexualism, the transforma- 

 tion of those individuals which are genetically females entirely into 

 males, results from matings of females of European races of the lowest 

 potency to males of Japanese races of the highest potency. Now if the 

 development of sexual characters depends upon the sex-factors acting 

 in conjunction with other elements in the genotype, the existence of sex- 

 factors or rather of systems of factors might operate in somewhat the 

 following fashion. In the female the sex-factor in a heterozygous condi- 

 tion acts in conjunction with a set of factors some of which are perhaps 

 sex-linked, although the number of chromosomes, 62 in this case, would 

 indicate that perhaps most of them were located in other chromosomes. 

 In a heterozygous condition then a certain sex-factor with those factors 

 with which it acts produces a female with the female set of secondary 

 sexual characters. In the homozygous duplex condition the same sex- 

 factor, presumably acting in conjunction with the same set of factors as 

 in the female, produces a male with the male set of secondary sexual 

 characters. If now there should be variations in the potency of a sex- 

 factor, as Goldschmidt assumes, then a strong sex-factor, or a sex-factor 

 which would interact more effectively in a given genetic environment 

 would have a tendency in the heterozygous condition to throw the reac- 

 tion more in the direction of that formerly conditioned by the existence 

 of the normal sex-factor in the homozygous condition. Such relations 

 would result in the formation of female intersexes, individuals genetically 

 females so far as the chromosome constitution is concerned, but develop- 

 ing male characters in a degree corresponding to the greater potency of 

 the introduced sex-factor as compared with the sex-factor normal for 

 the race in question. In case the introduced sex-factor, along with the 

 factors with which it normally interacts and which must never be dis- 

 regarded, equals in sex-determining power that of the normal sex-factor 

 in the duplex condition, then we might expect to get males of the chromo- 

 some constitution WZ. This appears actually to be the case in certain 

 of the experiments. Similarly a weaker potency of the sex-factor might 



