1920.] 



Study of Nesttimj Birds. 



871 



lotif^er useful ancestral fuuctiou. What this may have been, 

 with ray present knowledge, I cannot even guess. I do not 

 think it probable that it has any connection witli the 



Text-fiffure 14. 



-> / 



B. 



To show position of embryos within the ^'^^^. The arrows indicate 

 the point at which the shell is first chipped. 

 A. Nightjar {Caprimnlijns eiiropceus). 

 V>. Eidei'-Uucli {Somateria mollissimn). 



C. Kook ( Corvtts fnujUcijus). This position is more or less typical of 

 most Passerine birds. 



position of the embryo in the egg, although, so far as my 

 experience goes, this is somewhat unusual. The head is 

 tucked down in such a way that the bill and nostriU are 



