OBSERVATIONS AND DEDUCTIONS 27 



(14) If the hybrids be mated with the smallest group 

 in a set of their progeny, as many different kinds will 

 be produced as there are groups produced when the 

 hybrids are mated with each other, but each will 

 contain equal numbers of individuals. For instance, if 

 the monohybrid Xx be mated with its recessive, the 

 materials offered are 



X X. 



X X. 



and, X and x in the hybrid having equal chances of 

 combining with x in the recessive, equal numbers of the 

 two kinds Xx and xx must be produced. Again, if the 



Xx 



dihybrid ^ be mated with the smallest group, which is 



a double recessive, the materials offered are 



X x. 



.X X. 



,Y y. 



•y y- 



and equal numbers of the combinations Xx and xx will 

 be formed ; but, as equal numbers of the combinations 

 Yy and yy are formed at the same time, half of each of 

 the combinations Xx and xx will carry the combination 

 Yy while the other half will carry yy, and there will be 

 four different kinds in all equal in number, thus : 



