The skeleton of a Deer--(_Pander and D’Alton_), 21 Muscular cycle in the act of flexing the arm, 25 Screws formed by the bones of the wing of the bird, the bones of the anterior extremity of the Elephant, and the cast of the interior of the left ventricle of the heart, 28 The muscular system of the Horse--(_Bagg_), 30 The feet of the Deer, Ornithorhynchus, Otter, Frog, and Seal, 34 The Red-throated Dragon, 35 The Flying Lemur, 35 The Bat, 36 Chillingham Bull with extremities describing figure-of-8 movements, 37 Double waved tracks described by Man in walking, 39 Horse in the act of trotting, 41 Footprints of the Horse in the walk, trot, and gallop-- (_Gamgee_), 43 Skeleton of the Ostrich--(_Dallas_), 47 Ostriches pursued by a hunter, 48 Skeleton of Man, 55 The positions assumed by the extremities and feet in walking-- (_Weber_), 59 Preparing to run--(_Flaxman_), 62 The skeleton of a Perch--(_Dallas_), 65 The Salmon swimming leisurely, 65 Swimming of the fish according to Borelli, 67 Swimming of the fish according to the Author, 68 The Porpoise and Manatee, 73 The skeleton of the Dugong--(_Dallas_), 74 The Seal, 74 The Sea-Bear, 76 The elliptical, looped, and spiral tracks made in swimming, 81 The several attitudes assumed by the extremities in swimming in the prone position, 82 Overhand swimming, 85 Side swimming, 86 Swimming of the Turtle and Triton, 89 Swimming of the Little Penguin, 91 Sub-aquatic flight or diving, 94 The feet of the Swan as seen in the open and closed condition, 96 The foot of the Grebe with swimming membrane--(_Dallas_), 97 Double waved track described by the feet of swimming birds, 97 The flight of the Flying-fish, 98