1. Sladen, W. J. L., Ibis, 94, 541 (1952).
2. Andrew, J. D., and Roberts, J. M., Ibis, 94, 540 (1952).
3. Stonehouse, B., Nature, 169, 760 (1952).
4. Murphy, R. C., “Oceanic Birds of South America” (Amer. Mus. Nat. Hist., New York, 1936).
5. Sapin-Jaloustre, J., and Bourlière, F., Alauda, 19, 65 (1951).