RESULTS. 



11 



TABLE 4. Determinations of the skin color of Fi hybrids between whites and negroes. Cont'd. 



II. JAMAICA. 



A grandmother. Pigment has faded. 



TABLE 5. Summary. 



Corresponding with the difference in skin color of the parents, a 

 matter that we have already discussed, there is seen to be an evident 

 difference in the skin color of the FI hybrids. The very dark negro 

 strain produces, on the whole, the darkest offspring, with a mean 

 value of about 35 per cent N. The hybrids from the lighter strain 

 have a mean value of about 26 per cent N. 



IV. SKIN COLOR OF THE CHILDREN OF Two MULATTOES THE Fj 



GENERATION. 



The second generation of hybrids is the one which, in modern 

 studies in heredity, is relied on to give the key to the number of factors 

 involved in the production of any characteristic; so we look to it with 

 especial eagerness. Unfortunately, however, the mating of two strict 

 mulattoes is not common, so that the total number of cases available 



