SEXUALITY 685 



2. Reduction of systems of multiple gamete types to two sexes. As 

 earlier set forth, the reduction of the multiple gamete types in an inter- 

 breeding system to two sexes is based on the assumption that the two 

 sexes in any one race or species are fundamentally the same as the two 

 in any other race. In the case of C. paupera, in which six types of gametes 

 were found in the same natural source, it is presumably assumed that 

 three races, each with the same two sexes, were here living together. It 

 is important to recognize clearly that this view is based on Hartmann's 

 theory; it is not an observation or an induction from observation. Chem- 

 ical analysis of the sex stuffs shows that reduction of the eight gamete 

 types in the eugametos-paupera group of species to two qualitatively di- 

 verse sexes cannot be made on this basis, for the differences among the 

 eight sex stuffs are exclusively quantitative. The "tension" assumed to 

 bring the gametes together is held to be of two kinds. One kind is purely 

 chemotactic and due to the sex stuffs; this brings the gametes into con- 

 tact. It is clearly a quantitative phenomenon, dependent upon differences 

 in relative proportions of cis and trans dimethyl crocetin. The other kind 

 of tension determines whether gametes that have been brought into 

 contact will unite in copulation. The evidence for this, together with 

 considerations that render the conclusion less certain, was set forth on 

 page 682. However, if an unknown factor determining union in 

 copulation exists, it appears to act in the same quantitative way as the 

 sex stuffs, for copulation takes place between any two gamete types that 

 produce sex stuffs sufficiently diverse to attract each other. Consequently, 

 there are no observations justifying or even suggesting the introduction 

 of the concept of two qualitatively diverse sexes; all the observations 

 point directly to a system of multiple, quantitatively diverse sexes. 



In one respect the preceding account may not fairly represent Moe- 

 wus's views. The two sex stuffs may be taken as indices of two qualita- 

 tively diverse sex tendencies or potencies, cis demethyl crocetin being the 

 manifestation of the -|- sex potency, and trans dimethyl crocetin of the 

 — sex potency. In four of the eight types of gametes, the -|- sex potency 

 prevails, for these types produce more cis than trans; and this prevails 

 to different degrees in each type. In this sense these four types of gametes 

 may be considered as different strengths or valences of the -|- sex. Cor- 

 respondingly, the remaining four types could be considered four diverse 

 valences of the — sex. This view is in accord with that part of Hart- 



