This was probably one of the last sheets to be compiled during Leonardo’s collaboration with Marcantonio della Torre, and at one point he states ‘this winter of 1510 I believe I shall finish all this anatomy’. Along with general statements about the muscles of the limbs, Leonardo reminds himself to ‘depict the foot of a bear, a monkey and other animals, inasmuch as they differ from the foot of a man; and also put in the foot of some bird’.