September 9, 1921] 



SCIENCE 



225 



in predicting the record of the second year. 

 The criterion has already been considered 

 in relation to the prediction of first year egg 

 record.^ While our immediate purpose is the 

 2 Harris, Blakeslee and Kirkpatrick, Genetics, 

 3: 42-44, 49-56, 1918. 



consideration of the second year production 

 of birds which did and of those which did not 

 lay during given months of the first year, 

 it seems desirable to give the mean first 

 year productions of these birds as well. For 

 comparison the results deduced from the data 



MEAN ANNn.lL PRODUCTION FOR FIRST AND SECOND YEAR FOR BIRDS WHICH DID AND WHICH DID NOT LAY DURING 

 INDIVIDUAL MONTHS OF THE FIRST YEAR 



