Darwin, The variation of animals and plants under domestication. 2 vols. 2nd edn. New York, D. Appleton & Co. 1883. [first published London, John Murray, 1868 ),p322. On-line Here

" Here is a more curious case: white cats, if they have blue eyes, are almost always deaf......"

" This case of correlation in cats has struck many persons as marvellous. There is nothing unusual in the relation between blue eyes and white fur; and we have already seen that the organs of sight and hearing are often simultaneously affected. In the present instance the cause probably lies in a slight arrest of development in the nervous system in connection with the sense-organs......."

keywords: radicals melanin Ros