I WROTE on this subject in April, 1935 (antea, Vol. XXVIII., p. 322). I have pursued it for another year and have had considerably more information, all corroborative of the preceding, but in no wise tending to increase my estimated number of surviving young Rooks (Corvus f. frugilegus). I will call the birds under one year, juveniles. These are, of course, known by their feathered bill, which I f...

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