r -o GENETIC STUDIES ON THE SILKWORM 
cases and attempted to explain them on this hypothesis. Sturtevant (191 3c) 
proved that almost all cases of so-called multiple allelomorphism can be con- 
sidered as cases of complete coupling, though he was inclined to advocate the 
former hypothesis. On the contrary, Punnet t (191 5), who is aware of the in- 
consistency of this hypothesis with the universally adopted one of "presence 
and absence," adopts the theory of coupling. 
The present case can not, however, be explained by the coupling hypothe- 
sis. To interpret the case as one of coupling, one would be forced to assume 
(1) that striped is SM in genetic constitution, in which S and M are complete- 
ly coupled; (2) that moricaud is sM; (3) that double recessive is sm. The 
first assumption is evidently inconsistent with the fact mentioned before that 
the stripedd oes not involve the M factor at all, the characteristics of which must 
come to view if present. It follows that the case before us is a peculiar ex- 
ample of multiple allelomorphism which can not be explained by the theory 
of complete coupling. It does not, however, clash with the presence-absence 
hypothesis, if we assume a complete repulsion between S and M as was done 
above. 
IV. COUPLING, REPULSION, AND SEXUAL DIMORPHISM OF 
GAMETIC SERIES." 
So far as characters are not sex-limited, the gametic distribution is 
generally assumed to follow an identical system in both sexes. The hybrid 
males and females give the offspring nearly in the same ratio when crossed 
with double recessive. A sharp contrast to this general rule was, however, 
discovered in the correlated inheritance of the cocoon colour and the larval 
marking. These characters are associated in such a manner that the associa- 
tion is partial in the male, and complete in the female, a fact of deep interest 
in connection with the genetics of sex and "gametic reduplication." 
1 ) Preliminary communications on this subject are found in two of my previous papers (19143,1^. 
An article containing more detailed statements was sent to the Zeitschrift f. ind. Abst. it. Vererbungs- 
lehre in April of 1914 through the kindness of Prof. BAUK, and the proof was read by Prof. Hatta. 
But I do not know whether the number of the journal containing the article has been published or not, 
for it was about that time that the great war broke out. 
