Key to the Species. 



A. Plumage principally grey : 



a. Bill blackish ; legs red : 



a' No white band across tail ... ... ... C. livia. 



6', A white band across tail ... ... ... ... C. rupestris. 



6. Bill and legs yellowish ... ... ... C. eversmanni. 



B. Plumage principally white ... ... ... G. leuconota. 



COLUMBA LIVIA. 



Key to the Subspecies. 



A. Lower-back white ... ... ... ... C. I. livia. 



B. Lower-back grey ... ... ... C.l. intermedia. 



