iMiF.mr.wt }■; or < <>u>h> ix cattle 



21 



over white pea fowls. The gorgeous hues of the common 

 pea fowl are due both to pigments and to defraction and 

 it would he interesting to know whether the white pea 

 fowl has lost its pigments or defraction surfaces, or both. 



Animals of heavy pigmentation— as the blackbird, 

 the crow and the negro— are said to be more subject to 

 pre senile and albinic white than others less heavily pig- 

 mented. Enzymes may be inhibited or destroyed by an 

 excess of their own products. May it be indeed that the 

 antibody (YV) is itself a product of the determiner (N)1 



To throw further light upon the whole problem, among 

 other things, a careful study should be made of the be- 

 havior in inheritance of the age of graying of the hair 

 and beard in man. If the conclusion of this paper pn- 



will be found to be dominant over the later manifestation 

 of the same phenomenon. It is further anticipated that 



tic coat-color types are defined. As previously stated, the 

 striking fact is this: The roan of type No. 3 (which is 

 reciprocallv colored as compared with the ordinary color 

 pattern of 'cattle, is ,cv. observed, and <,uite probably 



ently jh follows: The antibody inhibiting and destroying 



flank, heart girth, forehead, and progresses system 

 irally through the area- of Set L> (roughly underli 



following scheme: 



Vol. XLIV, p. 501. 



