364 Mendel's Experiments 



fertilisation, since sixteen individuals are included in the 

 series. Therefore the participators in the fertilisation are 



Pollen cells AB + AB + AB + AB + Ab + Ab + Ab+Ab+ 

 aB + aB + aB + aB + ab + ab + ab + ab. 



Egg cells 



b + ab + ab. 



In the process of fertilisation each pollen form unites on an 

 average equally often with each egg cell form, so that each 

 of the four pollen cells AB unites once with one of the 

 forms of egg cell AB, Ab, aB, ab. In precisely the same 

 way the rest of the pollen cells of the forms Ab, alt, ab 

 unite with all the other egg cells. We obtain therefore 



AB AB AB AB Ab Ab Ab Ab 



" ~ "~ + + * + H 



AB ' Ab aB ab * AB l Ab aB * ab 



aB aB aB aB ab ab ab ab 



1 ~i "i r> H 7~ T /t D ~f ~/TL ~J 7> T ~~7 > 



^?c? ^i ^/ *d. o ai^> ao 



or 



AB + ABb + AaB + AaBb + ABb +A&+ AaBb + Aab + 

 AaB + AaBb + aB + aBb + AaBb + Aab + aBb + ab = AB + 

 A6 + a + a6 + 2 ABb + 2aBb + 2 AaB + 2 Aab 



In precisely similar fashion is the developmental series 

 of hybrids exhibited when three kinds of differentiating 

 characters are conjoined in them. The hybrids form eight 

 various kinds of egg and pollen cells ABC, ABc, AbC, 

 Abe, aBC, aBc, abC, abc and each pollen form unites 

 itself again on the average once with each form of egg cell. 



The law of combination of different characters which 

 governs the development of .the hybrids finds therefore its 

 foundation and explanation in the principle enunciated, 

 that the hybrids produce egg cells and pollen cells which 

 in equal numbers represent all constant forms which result 

 from the combinations of the characters brought together 

 in fertilisation. 



* [In the original the sign of equality (=) is here represented by +, 

 evidently a misprint.] 



