No. 635] SHORTER ARTICLES AND DISCUSSION 543 



II. The Total Relationship Coefficient 

 To measure the total degree of relationship during a numher 

 of generations I propose to use a total relationship coefficient 

 based on the same common principles as the total inbreeding 

 coefficient. 



The areas to be compared are the area included by the rela- 

 tionship curve (corresponding to the inbreeding curve) and 

 the area included by the maximum relationship curve. Now the 

 maximum values of the coefficient of relationship are 50 in every 

 generation beginning at K x and the area in question is for that 

 reason simply 50 times the number of generations involved. 



The formula of the total relationship coefficient for n genera- 

 tions is then the following: 



K _ lOOsJ^ 1 _ 2z£i' 



III. Total Relationship Inbreeding Index 

 To indicate the proportion of the inbreeding that is due to 

 relationship between the sire and dam of the individual, whose 

 pedigree is being examined, I wish to propose a single numerical 

 expression, the total relationship inbreeding index indicating 

 the proportion of the area included by the relationship curve 

 to the area included by the inbreeding curve, the formula being 

 the following: 



Calculation of the Coefficient Indicating the Degree of Inbreed- 

 ing and Relationship in the Pedigree of the Jersey Bull 

 King Melia Rioter 14th (103901) 

 To show the calculation and significance of the described co- 

 efficients I have selected the pedigree of King Melia Rioter 

 Fourteenth including eleven generations. Table I gives the 

 TABLE T 



Z x = 25.00 

 Z 2 =25.00 



Z< as 50.00 

 Z s = 71.88 



