Snake skeleton

A snake skeleton consists primarily of the skull, vertebrae, and ribs, with only vestigial remnants of the limbs. The skull of a snake is a very complex structure, with numerous joints to allow the snake to swallow prey far larger than its head. The typical snake skull has a solidly ossified braincase, with the separate frontal bones and the united parietal bones extending downward to the basisphenoid, which is large and extends forward into a rostrum extending to the ethmoidal region. The nose is less ossified, and the paired nasal bones are often attached only at their base. The occipital condyle is either trilobate and formed by the basioccipital and the exoccipitals, or a simple knob formed by the basioccipital; the supraoccipital is excluded from the foramen magnum. The basioccipital may bear a curved ventral process or hypapophysis in the vipers. The prefrontal bone is situated, on each side, between the frontal bone and the maxilla, and may or may not be in contact with the nasal bone. The postfrontal bone, usually present, borders the orbit behind, rarely also above, and in the pythons a supraorbital bone is intercalated between it and the prefrontal bone. The premaxillary bone is single and small, and as a rule connected with the maxillary only by ligament. The paired vomer is narrow. The palatine bone and pterygoid are long and parallel to the axis of the skull, the latter diverging behind and extending to the quadrate or to the articular extremity of the mandible; the pterygoid is connected with the maxillary by the ectopterygoid or transverse bone, which may be very long, and the maxillary often emits a process towards the palatine, the latter bone being usually produced inwards and upwards towards the anterior extremity of the basisphenoid. The quadrate is usually large and elongate, and attached to the cranium through the supratemporal (often regarded as the squamosal). In rare cases, (Polemon) the transverse bone is forked, and articulates with two branches of the maxilla.