![]() ![]() Its apex joins anteriorly with the presphenoid and its broad posterior end is connected with the basioccipital by a thin plate of cartilage.ĭorsal surface of basisphenoid has a depression, the sella turcica, in which pituitary gland is placed. It consists of five bones, a triangular basisphenoid on the mid-ventral side, alisphenoids on lateral sides and two parietals and interparietal on the dorsal side.īasisphenoid is a flat, median triangular cartilage bone. On lateral sides, both are separated from each other by auditory capsules and squamosals. It is present in front of occipital segment. The occipital condyles articulate with the facets of the first vertebra, the atlas. Supraoccipital articulates in front with the parietals, and on lateral sides with the squamosals and periotics.īasioccipital anteriorly articulates with basisphenoid and laterally with penotics. The bone making the dorsal boundary of the foramen magnum is flat shield-like square-shaped supraoccipital, the ventral boundary is marked by a flat bone, the basic occipital, and the lateral boundaries are marked by a pair of exoccipitals.Įach ex-occipital bears a prominent oval or a somewhat elongated occipital condyle and also gives off a downwardly directed paroccipital process which lies in close contact with postero-ventral surface of tympanic bulla. It consists of four cartilaginous bones completely fused together and encircling a large passage, the foramen magnum, through which spinal cord comes out. It is the hindermost part of the cranium. The various bones constituting the cranium can be grouped into three segments, a posterior occipital segment, middle parietal segment and anterior frontal segment. Visceral skeleton includes the upper and lower jaws and hyoid apparatus. Sense capsules (olfactory, auditory and orbital) closely attached with the cranium, andģ. ![]() The skull of the rabbit can be divided into:Ģ. Canines are absent leaving a space, called diastema. Teeth are diphyodont (milk and permanent) and heterodont (different types). Premaxillae, maxillae and dentaries bear the thecondont teeth (teeth embedded in sockets). Prefrontal, postfrontal, parasphenoid and quadratojugal are lacking. Jaws suspensorium is craniostylic, i.e., dentary, articulates with the cranium (skull) by squamosal.ġ3. Only a single bone, the dentary, forms one half of the lower jaw.ġ2. Turbinal bones are much folded and, thus, increases the olfactory surface of nasal chambers.ġ1. Otic bones, prootic, epiotic and opisthotic, are fused to form a single periotic.ġ0. The articular and quadrate of the jaws become separated and free, and form malleus and incus respectively (two ear-ossicles of the three). The auditory capsules are formed by the union of periotic and tympanic forming a swollen tympanic bulla.Ĩ. ![]()
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