Genie Control of Development 339 



ics of sex. We shall show that the genetic facts may have been misin- 

 terpreted. For our present discussion we will extract that part of the 

 alleged facts which is connected with dosage, without trying to inter- 

 pret the sex-determining mechanism and its assumed chemistry. 



The main points, leaving out confusing details, are as follows. 

 There are two different, closely linked loci in what may be called an 

 autosome: gathe"^ and gathe*""**"^. Their function is the control of 

 enzymes or enzyme systems which perform, respectively, the synthesis 

 of cis- and trans-dimethylcrocetinester from the substrate cis- or trans- 

 crocin. These two esters are the -f and — substances which permit 

 copulation (the mating types). A female cell must produce more cis- 

 than trans-ester in order to be able to copulate, and a male cell more 

 trans- than cis-ester. Femaleness and maleness as such are controlled 

 in Moewus' scheme by two loci, F and M, not allelic and located in 

 another pair of chromosomes which we might call X and Y. (This 

 point will be contested later. ) They are closely linked with some other 

 loci which, in the F-chromosome, produce isorhamnetin; this deter- 

 mines the cell as female. Similar loci in the M-chromosome produce 

 paronin, the male-determining substance. Now F and M are not sex 

 determiners, but they regulate the relative amount of cis- and trans- 

 ester produced by the gathe loci, the relation of which determines the 

 chance for copulation, namely, more cis for the female cell and more 

 trans for the male cell. We assume here that this complicated system 

 has really been found and correctly interpreted in its strange inter- 

 play of sex determination and sexual compatibility. (I personally am 

 very skeptical, but Sonneborn has accepted it. ) Just now the Hartmann 

 school is repeating these experiments. Thus far they have been unable 

 to duplicate them, and they find a completely different chemism 

 (communication by letter; and Forster and Wiese, 1954a). 



Now we come to our real topic. F and M are found to have a 

 series of alleles of different valency, or potency, conferring upon the 

 cells the intermediate copulation conditions which Hartmann has 

 called relative sexuality. This, then, is clearly a parallel to the 

 different valencies or strength in the F and M of Lijmantria, which 

 also act like a set of alleles. Moewus distinguished four grades for 

 both F and M with reciprocal action, as the following table shows: 



cis:trans cis:trans 



Fi 65:35 Ml 35:65 



F2 75:25 M2 25:75 



F3 85:15 M3 15:85 



F4 95: 5 M4 5:95 



