The strength of the claws, in like manner, and the mobility of the paws and toes, have a necessary relation to the forms of the bones in the feet, and the distribution of the muscles and tendons by which they are moved. As the bones of the forearm are articulated with the humerus, no change can be made in the form and structure of the former without occasioning correspondent changes in the form of the latter. The shoulder-blade also, or scapula, requires a correspondent degree of strength in all carnivorous animals, while the play and action of the several parts are dependent on the muscles which set them in motion, and the impressions formed by these muscles still further determine the forms of all these bones. Again, the shape and structure of the teeth regulate the forms of the condyle, of the scapula, and of the claws, in the same manner as the equation of a curve regulates all its other properties;—and, as in regard to any particular curve, all its properties may be ascertained by assuming each separate property as the foundation of a particular equation, in the same manner a claw, a shoulder-blade, a condyle, a leg or arm bone, or any other bone separately considered, leads to the discovery of the characters of teeth to which they have belonged; and reciprocally from the teeth we are enabled to discover the structure and forms of the other bones. Thus, conducting his investigations by a careful survey of the bones and organs individually and separately, the skillful anatomist was enabled to reconstruct the whole animal to which they severally had belonged. The orders likewise and subdivisions of herbivorous, ruminant, hoofed, and cloven-hoofed animals, he determined with equal precision, and found to result from the same constant laws of organization. By employing the method of observation, where theory was no longer able to direct his views, Cuvier was furnished with other astonishing results. The smallest fragment of bone, even the most apparently insignificant apophysis, he found to possess a fixed and determinate character, relative to the class, order, and genus of the animal to which it belonged; insomuch that, when he observed merely the articulating extremity of a well-preserved bone, he could at once ascertain the species as certainly as if the entire animal had been before him. Proceeding after this method, assisted by analogy and exact comparison, Cuvier has been enabled to determine the fossil remains of seventy-eight different quadrupeds, in the viviparous and oviparous classes. Of these, forty-nine are distinct species hitherto unknown, twenty-seven of which are referable to seven new genera, and the other twenty-two new species belong to sixteen genera, or sub-genera, already known; while the whole number of genera and sub-genera, to which the fossil remains of quadrupeds investigated belong, are thirty-six, including those both of known and unknown species; some hoofed animals not ruminant, and some ruminant—others