The tibia and fibula are united inferiorly, the tympanic bulla is hollow and the infra-orbital foramen narrow.
Moreover, the crowns of the hinder cheek-teeth are taller, and more distinctly crescentic, both feet are two-toed, the ulna and radius are fused, and the fibula is represented only by its lower part.
The distal half of the fibula is very slender and normally does not reach the ankle-joint; it is attached to the peroneal ridge of the tibia.
In the fore-limb the upper and lower series of carpal bones scarcely alternate, but in the hindfootthe astragalus overlaps the cuboid, while the fibula, which is quite distinct from the tibia(as is the radius from the ulna in the fore-limb), articulates with both astragalus and calcaneum.
Reduction of the fibula till nothing but its lower extremity remains.
Lower extremity of the fibula represented by a distinct malleolar bone articulating with the outer surface of the lower end of the tibia.
The odontoid process of the second vertebra is pig-like: and the tibia and fibula and radius and ulna are severally distinct.
In the Sciuridae the two main bones (tibia and fibula) of the lower half of the leg are quite separate, the tail is round and hairy, and the habits are arboreal and terrestrial.
The humerus often has a foramen (entepicondylar) on the inner side of its lower end; the tibia and fibula may be separate or united; but the scaphoid and lunar of the carpus are also united, while the centrale is free.
The tibia and fibula are fused at their upper and lower ends.
Of these Ctenodactylus and Pectinator are characterized by the union of the incus and malleus of the internal ear, the free fibula and the almost rootless cheek-teeth.
The incisive foramina are large and usually confluent; the bony palate is very narrow from before backwards; there is no alisphenoid canal; the fibula is welded to the tibia, and articulates with the calcaneum; and the testes are permanently external.
The fibula is complete, thickest at its upper end, where it generally unites with the tibia.
The femur has a small third trochanter, the radius and ulna and tibia and fibula are respectively separate, at least in the young, and the fibula articulates with the astragalus.
On the other hand it appears that the smaller bone of the leg (fibula) was welded to the larger one (tibia), and that its upper portion had disappeared.
The hind-limb is typically avine, with intertarsal joint, distally reduced fibula, and the three elongated metatarsals which show already considerable anchylosis; reduction of the toes to four, with 2, 3, 4 and 5 phalanges; the hallux is separate, and as usual in recent birds posterior in position.
In both groups, for instance, the lower part of the hind-leg is formed by a long, slender cannon-bone, or metatarsus, terminating inferiorly in triple condyles for the three long and sharply clawed toes, the resemblance being increased by the fact that in both cases the small bone of the leg (fibula) is fused with the large one (tibia).
Further, at an early stage of development the fibula is a complete and separate bone, while the three metatarsals, which subsequently fuse together to form the cannon-bone, are likewise separate.
(b) The second of these early records is the inscription on a gold fibula found at Praeneste and published in 1887.
The inscription is probably not older than that on the fibula from Praeneste, but has the additional interest of being undoubtedly couched in the Latin of Rome.
The British Museum possesses a fine fibula of silver decorated with a simple pattern in niello and thin plates of repousse gold.
The fibula is reduced to a mere rod-like rudiment of the upper end.
Radius confluent with ulna, and tibia with fibula; tarsus (astragalus and calcaneum) elongate, forming an additional segment in the hind limb.
In the Ecaudata also, the tibia and fibula coalesce into one bone, and two or three small bones on the inner side of the tarsus form what has been regarded as a rudimentary digit or "prehallux."
The orbit is surrounded by a bony ring; the ulna and radius in the fore, and the tibia and fibula in the hind-limb are united, and the feet are of the types described above.
The femur is short, and the tibia and fibula of great length, as is the foot, the whole of which is applied to the ground when the animal is at rest in the upright position.
In the squirrels and porcupines the tibia and fibula are distinct, but in rats and hares they are united, often high up. The hind foot is more variable than the front one, the digits varying in number from five, as in squirrels and rats, to four, as in hares, or even three, as in the capybara, viscacha and agouti.
In both groups the tibia and fibula are separate.
In the Bathyergoidea the scaphoid and lunar of the carpus are separate, the tibia and fibula united and the clavicles normal.
The tibia and fibula are separate, but the scaphoid and lunar are united, and the clavicles are generally incomplete.