CORVIDAE. 



In the so-called cyanic eggs, i. e. eggs of a blue or bluish green 

 colour, biliprasin is either wholly absent or occurs in extremely 

 small quantities, the oocyan occurring purely or almost purely as 

 surface colour. 



The result of the examination of eggshell-mammillae of corone, 

 cornix and corone X cornix by W. von Nathusius, gives good 

 grounds for the suspicion that bastardization is of influence on the 

 size of the mammillae, and that of eggs of corone X cornix this 

 size lies between those of the two species. 



In 1907 Baron R. Snouckaert van Schauburg, LL.D., obtained 

 from the Province of Zeeland well characterized native bastard 

 eggs (now in my collection); these eggs, in conformity with reports 

 received from abroad respecting similar eggs, offer no external 

 points of difference from pure corone or cornix eggs. 



