With Huxley he became engaged in controversy with Richard Owen, who claimed that the human brain had unique structures not present in simians. Huxley had contradicted this at the British Association meeting at Oxford in 1860, which included a debate on evolution, and promised proof. He was among experts consulted by Huxley and gave demonstrations at Huxley's public lectures, using monkey brains rather than scarce ape brains. He published papers on the brains of four species of monkey, and at the 1862 meeting of the British Association in Cambridge, after Owen read a paper repeating his claims, stood up saying "I happen to have in my pocket a monkey's brain" and produced the object in question.