SUMMARY OF RESULTS AND CONCLUSIONS. 



Silkworms exhibit some characteristics which are alternative in 

 inheritance and which follow in their transmission exactly or with 

 more or less approximation Mendelian proportions. But some of 

 these characteristics are not very stable in their alternative and Men- 

 delian behavior. Other characteristics still are not discontinuous or 

 alternative in character or inheritance but are of the nature of fluctu- 

 ating variations and are strongly obedient to Galton's law of regression. 



Larval color-pattern differences are consistently and rigorously 

 alternative and Mendelian in inheritance; cocoon colors tend to be 

 alternative and Mendelian in behavior but are inconsistent as to dom- 

 inancy and recessiveness and numerical proportions, and may even 

 break down and blend, or one color be otherwise influenced or modi- 

 fied by the presence, in a mating, of another. 



Larval pattern and cocoon color characters do not except as coinci- 

 dences follow the same parent in dominance. In cross matings com- 

 bining opposed larval and cocoon characters dominance in larval pat- 

 tern may be with the paternal type, in the cocoon color with the 

 maternal, or vice versa, or both dominances may rest with the paternal 

 or with the maternal type. Dominance is a function of the character- 

 istic not of the parental influence. Dominance is also not a function of 

 sex or of bodily vigor. 



While in larval color-pattern characters the inheritance behavior 

 is rigorously alternative and Mendelian, dominance always being con- 

 sistent in relation to a given color-pattern as related to another, this 

 is not true of cocoon colors. With these characteristics differences 

 peculiar to strain (or race) and individual are marked. Strain and in- 

 dividual idiosyncrasies are real and important and thus sweeping 

 generalizations concerning the inheritance behavior of the cocoon colors 

 tending to class them unqualifiedly in the Mendelian category cannot 

 be made. The tendency is for them to behave in Mendelian manner, 

 but it is a tendency subject to numerous, marked and various incon- 

 sistencies and irregularities. 



In double matings, i. e. mating of one female with more than one 

 male, these males representing different types of larval and cocoon 

 characters, interesting modifications and interactions of influence are 

 to be noted. The reality of strain potency over character potency is 

 made manifest in these double matings. 



