114 MASS. EXPERIMENT STATION BULLETIN 199. 



in this experiment the daughters of non-broody hens are less broody than 

 the daughters of hens broody once, it would be unwise to generalize such 

 a conclusion, because of the very small number of indi\aduals involved. 



Table XII. — A Comparison of the Amount of Broodiness in the Daughters 

 of Non-broody Hens with those whose Mothers becmne Broody once. 



Number 

 of Instances 

 or In- 

 dividuals. 



Days of broodiness per individual, 



Days in each broody period, 



Broody periods per individual, 



Days in initial laying period, 



Eggs laid in initial laying period, 



Per cent production in initial laying period 



per individual. 

 Days in each laying period, . 



Eggs laid in each laying period, . 



Per cent production in each laying period. 



Eggs in each laying period per individual. 



Mothers not Broody j Mothers Broody once 

 IN Pullet Year. \ in Pullet Yeab. 



14 

 22 

 14 

 14 

 14 

 14 

 22 

 22 

 22 

 14 



Mean. 



31.64 



18.26 



1.79 



181 36 



106.93 



60.86 



38 23 



21.95 



65.20 



25.44 



Number 

 of Instances 

 or In- 

 dividuals. 



Mean. 



Since some birds become broody in their second or third lajdng years 

 that did not become broody in the first year, the question may be raised 

 as to whether or not a hen may ever be so constituted that it is impossible 

 for her to become broody. We have kept a few hens for four years with- 

 out evidence of broodiness, but this may not mean that these birds might 

 not have become broody if the proper stunulus had existed. There is 

 the further question as to whether the designation "non-broody" has 

 been accurately used for birds not broody in their pullet year. It might 

 be better to regard such cases as instances of delayed broodiness rather 

 than of the actual absence of broodiness. The delay in the appearance 

 of broodiness in some individuals certainly complicates matters greatly. 



The Interrelation of Several Broody Char-icters. 



The interrelations of several of the broody characters have been studied 

 in the 1913-14 flock by means of the coefficient of correlation. It should, 

 perhaps, be pointed out that the coefficient of correlation does not measure 

 the relationship between the characters as such, but relationship between 

 the numerical occurrence of such characters in the flock studied. This 

 limitation in the use of the coefficient of correlation is often forgotten. 

 Thus it is found that r between number of eggs laid in a year and total 

 days spent in broodmess is -f.l677± .0742. This value, as sho^\'n by 



