362 Matcnud Inheritance ami MendeUstn 



exception, normal and grey batches. Thus five matings of the normal 

 series from the divoltiae breed yielded 20 normals and 6 greys i 

 six matings of the grey series from the same breed similarly gave 25 

 normals and 35 greys. (See Table II.) 



The third generation of the normal series which were reared in the 

 spring of 1910 yielded all normal egged batches which when inbred 

 remained true to parents in subsequent generations : i.e. they became 

 homozygous. This was not the case in the grey series. Five matings 

 of the grey series in the spring of 1910 (third generation) gave 

 67 normals and 67 greys, in addition nine batches of a new variant 

 which we have as yet never observed in our breeds. 



This new variant is characterized by the thin translucent shell which 

 has fine wrinkles over it and by a shape a little longer than normal 

 eggs. Tliere is no depression iu the middle. We shall call this kind 

 of variant " B-grey," since it more resembles the grey form than the 

 normal ones. In the case of moths laying B-grey eggs the actual 

 number of eggs laid is always much smaller than the number laid by 

 moths laying eggs of normal colour, even though the parents belong to 

 the same batch. The worms which came out from the BG are so weak 

 that we can hardly get any moth and consequently we are unable to 

 trace the order of its inheritance. 



Of six grey matings of the grey series which were reared in the 

 summer of the same year (fourth generation), five again yielded 

 100 normals, 173 greys and G9 B-grey batches. One mating, on the 

 contrary, gave no normal eggs except the grey and B-grey, the 

 respective figures obtained being 7 and 36. 



The fifth generation derived from the grey mating, which in the 

 last generation yielded no normal batches, gave 245 batches in which 

 120 were grey, 106 B-greys, 5 mixture of grey and B-grey, and 4 

 which look like an intermediate form between normals and B-greys. 



Details of figures obtained iu each mating of each generation will 

 be seen in Tables II and III. 



From the results above quoted, we are able to say that, as in the 

 case of first and second series, both normal and grey characteristics 

 segregate from one another, and it is easier to get rid of the antagonistic 

 characters in the normal than in the grey. The appearance of the new 

 form which may probably be due to the new combination of allelomorphs 

 renders the phenomena of inheritance rather complicated. Hence if 

 we consider the G and BG forms as a single form, the results come in 

 the same category, which was mentioned in the former series of 

 experiments. 



