66 'Journal of Comparative Neurology and Psychology. 



evening bj lamp-light she huddled close to the father and preened 

 his breast and neck, sometimes preening her own feathers in that 

 spasmodic manner which is a sign of eros, and sometimes inter- 

 rupting these proceedings to give the nest-call coo. From this day 

 forth she did not cease to show her readiness and anxiety to mate. 



SUMMARY OF DEVELOPMENT. 



B'. Beginning of the Annuae Cycle. 



The age at which a ring-dove begins to breed depends upon the 

 season, for the tendency is in all cases to begin breeding in the 

 spring. Birds maturing in the autumn are delayed by the tendency 



