4 Pages in Charles Darwin's Library associated with "mental states - pleasure"

De la physionomie et des mouvements d'expression
By: Gratiolet, Pierre.
Publication info: Paris, J. Hetzel, 1865
Pages: Page 335
Elements of physiology
By: Müller, Johannes, - Baly, William,
Publication info: London, Taylor & Walton, 1838-1842
Volume: v.2
Pages: Page 1407 Page 1701
On the genesis of species
By: Mivart, St. George Jackson,
Publication info: London, Macmillan & Co, 1871
Pages: Page 196