![]() At the anterior margin it bears a median knob-like process which receives the hinder end of parasphenoid. On its antero-lateral sides it gives off a pair of basipterygoid processes which unite with the pterygoids at their free ends. It is a broad, flat and somewhat rectangular bone. The basisphenoid forms the floor of the cranium in the parietal region. The parietals articulate anteriorly with the frontals, posteriorly with the supraoccipital, on the sides with the post-orbitals and below with the epipterygoid. The supratemporal processes form the outer margins of the post-temporal fossae. Its postero-lateral angles are produced into supratemporal processes, each of which articulates with the quadrate, squamosal, supratemporal and paroccipital process of the exoccipital of its side. The two parietals are fused to form a single bone. It forms the roof of the cranium in the parietal region or segment. The parietal is a large flat bone on the postero-dorsal side of the cranium. The parietal segment comprises only two bones, parietals and a basisphenoid. All the bones of this region are fused forming a ring-like structure. Occipital segment articulates posteriorly with the atlas vertebra by the occipital condyle of the basioccipital. Each exoccipital has a combined juglar and condylar foramen for the exit of X, XI and XII cranial nerves and artery and vein.Įach exoccipital articulates with the supraoccipital, prootic and the basioccipital. Each exoccipital is produced on its outer side into a paroccipital process articulating with the supratemporal, squamosal, parietal and quadrate. It articulates anteriorly with the basisphenoid, laterally with the exoccipitals and prootics.Įxoccipitals surround the foramen magnum from its lateral sides. ![]() Basioccipital forms the floor of the hindermost portion of the cranium and posteriorly bears a single occipital condyle. ![]() It articulates anteriorly with the parietals and laterally with the prootics forming the post-temporal fossa. Supraoccipital is more or less rectangular forming the roof of the hindermost part of the cranium. It consists of four bones, i.e., the dorsal supraoccipital, the lower basioccipital and paired lateral exoccipitals. It encloses a large aperture foramen magnum in its centre. The occipital segment is the posteriormost part of the cranium. The cranium comprises three segments, i.e., the posterior occipital segment, the middle parietal segment and the anterior frontal segment. The cranium proper forms the posterior part of the skull and lodges the brain. The skull of Varanus may be divided into four main regions, viz., the cranium, sense capsules (auditory, optic and olfactory) and the visceral skeleton comprising the jaws and hyoid apparatus. ![]()
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