STUDIES IN THE EXPERTHENTAL ANALYSIS OF SEX. 577 
Studies in the Experimental Analysis of Sex. 
By 
Geoffrey Smith, 
Fellow of New College, Oxford. 
With Plate 30. 
1. On Mendelian Theories op Sex. 
The re-discovery of Mendel’s observations on lieredity, and 
the extended application of his ideas by such writers as 
Correns, Tscliermalc, and Bateson to every branch of life, has 
had a very profound influence on contemporary biological 
conceptions, and it is not surprising that the pi’oblem of sex, 
which has occasioned so many speculative theories in past 
times, has been brought under the focus of Mendelian 
research and subjected to its analysis. The conceptions of 
segregation, of allelomorphism, of heterozygotism, to employ 
the accepted terminology of Professor Bateson (1), seem 
admirably suited in their application to the phenomena of 
sex, because in .sexual reproduction we actually see that 
the sexual characters do segregate into two sharply separated 
sets of individuals, the males and the females, as if malcness 
and fenialeness were in some way allelomorphic to one another, 
while the occurrence of hermaphrodite forms and the latent 
presence in one sex of characters proper to the opposite 
sex indicate the phenomenon of heterozygotism or sex- 
liybridism. 
There is a further reason why Mendelian speculation has 
naturally turned in the direction of sex. So long as it was 
held that the sex of any animal or plant was not a question 
of inheritance or of a pre-determiued quality of the germ, 
