Autograph Letter Signed ‘Edward B.Poulton’, agreeing to lecture at the London Institution, suggesting as a subject ‘The methods by which animals conceal themselves”, for which he has a fine series of slides. 1 page 7 x 4 inches, with two lines and signature overleaf, in very good condition. Wykeham House, Oxford, 26 June 1891. Sir Edward Bagnall Poulton (1856 –1943), Darwinist, evolutionary biologist who was a lifelong advocate of natural selection. He invented the term sympatric for evolution of species in the same place, and in his book The Colours of Animals (1890) was the first to recognise frequency-dependent selection. Author of Charles Darwin and the Theory of Natural Selection (1896) and other works.