The Expression of the Emotions in Man and Animals a greater role for the higher cortical centres in the regulation of the emotional response, and touches on the theme of gender differences in emotional expression, anticipating the approach of sociologist Norbert Elias in "The Civilizing Process". In 1905, Sir Arthur Mitchell, a psychiatrist who had served as William A.F. Browne's deputy in the Scottish Lunacy Commission, published "About Dreaming, Laughing and Blushing", bridging some of Darwin's concerns with those of psychoanalysis. Freud's early publications on the symptoms of hysteria (with his influential concept of unconscious emotional conflict) acknowledged debts to Darwin's work on emotional expressionand Darwin's impact on psychoanalysis
The Formation of Vegetable Mould through the Action of Worms went the less controversial direction of the lowly worm. His network of correspondents and fans responded to his interest and "earthworm anecdotes began surfacing in his mountain of mail". He had been interested in earthworms "since his first fishing days at The Mount and flirting days at Maer". Still, other work constrained him. Broken off from "Descent", he had to finish his next work "The Expression of the Emotions in Man and Animals". By 1876, with his first grandson on the way, he felt his writing life was nearly over, with so much unfinished. He wanted to write on earthworms