C. A. Johns,
British Birds in Their Haunts
“ Eggs bluish green, mottled with ash-grey and olive.The Hooded Crow closely resembles the Carrion Crow, scarcely differing from it in fact except in colour. They are, however, perfectly distinct species, and for the most part exercise their calling in separate haunts. In Norway Hooded Crows are very abundant, to the almost total exclusion of the Carrion Crow and Rook, and, though not congregating so as to form a society like the last-named bird, they may be seen simultaneously employed in searching for food in groups which collectively amount to a hundred or more. ”
