Sept. 15, 191S Resemblance of Parents and Offspring of Sheep 



489 



Table IX(A). — Correlation between offspring and sires 



r=o.o527 ±0.0070. 

 Means of arrays of offspring : 



(i) When the sire is a single i. 3787 ±0. 0045. 



(2) When the sire is a twin i. 422o±o. 0057. 



(3) When the sire is a triplet i. 683 ±0. 045. 



Table IX(B). — Percentages of offspring in states I, 2, and j to correspond to states 



I, 2, and J of the sires 



While the same sort of tendencies are to be noted in the examination 

 of these tables as with Tables 11(A) and 11(B), it seems that the tendency 

 of twins to produce twins is less marked and that the correlation is 

 given by 



r = 0.0527 ± 0.0070. 



If we had excluded none of the offspring of large producing sires with an 

 abnormal proportion of recorded twins or singles, we should have obtained 



r — 0.0294 ± 0.0066. 



We think there is, however, little doubt that it would be improper to 

 include for purposes of calculation at least most of the cases we have 

 excluded. 



We may well note the increase in means of arrays for twin and triplet 

 sires. 



In order to examine a little more critically into the question whether 

 twin sires tend to have a larger number of twin offspring than do single 

 sires, we have invented an index number for each sire. This number is 



