English biologist (1825-1895) known as ‘Darwin's Bulldog’ for his advocacy of Charles Darwin's theory of evolution. ALS signed “T. H. Huxley,” three pages on two adjoining sheets, 4.5 x 7, June 2, 1894. Letter, in Huxley’s difficult to decipher hand, sending thanks for a book on Psychology. In very good condition, with uniform toning, some brushing to a few words of text, and erased pencil notations and scattered soiling to first page. RRAuction COA.