It is a curious and interesting fact, affording a remarkable illustration of the close adherence to a uniform plan which has been observed in the construction of the various animals, that, in no instance, does this toe contain more than two bones. Even in those creatures, as the SEAL (fig. 2), in which it attains to greater length than any of the other sprawling digits, it contains the same number of bones as in man, its extraordinary length being attained by an elongation of the two bones, not by the addition of a third. And in those animals, as certain Lizards (fig. 3), where the number of bones in the other toes is increased to 4 or even 5, the number in the first, or inner, toe is still no more than two. The same rule applies to the fore limb; the number of bones in the inner digit, which, in man and monkeys, is called the “thumb,” is in no case more than two. In some animals, as will be mentioned again, there is only one bone in this digit, and in some the digit is wanting altogether; but in none does it contain _more_ than _two_ bones. This reminds me of a still more remarkable instance of adherence to a particular number of bones. In the mammalian group of animals the _neck_, with only one or two exceptions, contains _seven_ bones, neither more nor less. Whether it be the long neck of the GIRAFFE, or the short neck of the MOUSE, the BAT, or the PORPOISE, each consists, like the neck in MAN, of seven bones. For what reason a particular number should be thus rigidly observed, it is not easy to say. Of the seven tarsal bones the uppermost (fig. 1) is called the _astragalus_, from a supposed resemblance to a die. It is the middle bone of the instep. Above, it is jointed with the leg-bones; behind, it is connected with, and rests upon, the _heel-bone_, which is the largest bone in the foot. The bone which lies immediately in front of the astragalus, and supports it in this direction, is called the _scaphoid_, or boat-like, bone. In front of it are three _wedge-bones_, each of which is connected with one of the metatarsal bones of the inner three toes. On the outer side of the wedge-bones, connected with the metatarsals of the two small toes, and locked in between them and the heel-bone, is the _cuboid_ bone.