THE ORIGIN OF GYNANDROMORPHS. 89 



adopted the cytoplasmic agency. In moths there is present, in certain 

 species, a W sex-chromosome analogue of the Y of Drosophila that 

 is always carried along the female line. If this chromosome carries 

 factors it becomes one of the conditions of the result and the eggs will 

 always be under its influence, and hence differ from the spermatozoa 

 by a constant difference. This assumed difference might account for 

 the fact that in reciprocal crosses the results differ and certain phases 

 of the inheritance consistently follow the egg. There would be no 

 theoretical objection to calling this difference " factors for femaleness." 

 If crossing-over took place between the W and the Z chromosomes, 

 however, this constancy would disappear. Until critical evidence 

 can be obtained, such as the loss of the W chromosome from a line, 

 there is no way of proving or of disproving the cytoplasmic versus 

 W-inheritance hypothesis. 



In regard to the numerical values that Goldschmidt assigns to M 

 and F, it is obvious that these are from the nature of the case arbitrary, 

 such values being assumed as will give a consistent interpretation. 

 Whether this mode of treatment has the advantage of a quantitative 

 procedure, as claimed, is not so obvious, for the values are simply 

 assigned to the data and are not given by any outside common measure, 

 such as the chemist or physicist uses in quantitative work. If, then, 

 the values are only numerical assumptions, the treatment is not, as 

 Goldschmidt thinks, lifted above the symbolic handling of the problem 

 of heredity, but stands on the same footing as all Mendelian procedure. 

 If the numerical values assumed give consistent results when tested 

 in other crosses where other numerical values have been assigned, there 

 is an undoubted value in handling the problem in this way quite 

 irrespective of the question as to what a quantitative treatment may 

 mean. 



As stated, Goldschmidt interprets his results as depending on a 

 quantitative relation of the opposing factors for femaleness and for 

 maleness. If the quantitative difference between the factors is suffi- 

 ciently great in one direction the individual is a male ; if in the opposite 

 direction it is a female. If the difference is not sufficiently great either 

 way an intersex develops. If the quantity of the female factors were 

 greater at the beginning a female intersex results; if the quantity of the 

 male factor were greater at the beginning a male intersex develops. 

 Both kinds of intersexes grade in different crosses all the way from 

 nearly normal females to nearly normal males or from nearly normal 

 males to nearly normal females. In each series the sequence in which 

 the characters change towards those of the opposite sex is the reverse 

 of the order in which they develop in the individual. "The last organs 

 to differentiate in the pupa and the first to be intersexual are the 

 branching of the antennae and the coloration of the wings. The first 

 imaginal organ differentiated in the caterpillar and the last hi the series 

 to be changed toward the other sex is the sex-gland. And if we apply 



