A New View of Darwinism

I AM much obliged to Mr. Howorth for his courteous expressions towards me in the letter in your last number. If he will be so good as to look at p. 111 and p. 148, vol. ii. of my ``Variation of Animals and Plants under Domestication,'' he will find a good many facts and a discussion on the fertility and sterility of organisms from increased food and other causes. He will see my reasons for disagreeing with Mr. Doubleday, whose work I carefully read many years ago.