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[[File:Cambridge Natural History Mammalia Fig 014.png|thumb|right|400px|'''Lateral View of a Canine Skull''', Cambridge Natural History Mammalia Fig 014. (C.occ - Occipital condyle; F - frontal; F.inf - infra-orbital foramen; Jg - zygomatic arch; Jm - premaxilla; L - lachrymal; M - maxilla; Maud - external auditory meatus; Md - mandible; N - nasal; P - parietal; Pal - palatine;  Pt - pterygoid; Sph - sphenoid; Sq - squamosal; Sq.occ - supraoccipital; T - tympanic. (From Wiedersheim's Comparative Anatomy.) ]]  

[[File:Cambridge Natural History Mammalia Fig 014.png|thumb|right|400px|'''Lateral View of a Canine Skull''', Cambridge Natural History Mammalia Fig 014. (C.occ - Occipital condyle; F - frontal; F.inf - infra-orbital foramen; Jg - zygomatic arch; Jm - premaxilla; L - lachrymal; M - maxilla; Maud - external auditory meatus; Md - mandible; N - nasal; P - parietal; Pal - palatine;  Pt - pterygoid; Sph - sphenoid; Sq - squamosal; Sq.occ - supraoccipital; T - tympanic. (From Wiedersheim's Comparative Anatomy.) ]]  

The shape and size of the skull varies widely between different breeds of dog. Dogs have different skull lengths depending on breed. '''Mesocephalic''' dogs have average conformation whilst '''dolichocephalic''' dogs have longer skull lengths and '''brachycephalic''' dogs have shorter skull lengths. [[Image:Pug skull.jpg|thumb|left|150px|'''Brachycephalic skull''', nabrown, 2008]] The skull is divided into three broad components - the neurocranium, the dermatocranium and the viscerocranium.

The shape and size of the skull varies widely between different breeds of dog. Dogs have different skull lengths depending on breed. '''Mesocephalic''' dogs have average conformation whilst '''dolichocephalic''' dogs have longer skull lengths and '''brachycephalic''' dogs have shorter skull lengths. [[Image:Pug skull.jpg|thumb|left|150px|'''Brachycephalic skull''', nabrown, 2008]] The skull protects the brain and head against injury and supports the structures of the face. The skull is comprised of many individual bones that are normally fused together in adults to form a strong single structure. The process of bone fusion is called endochondral ossification and represents the process where the various plates of cartilage within the skull are converted to bone.  

The skull comprises of many individual bones that are fused together to form a strong single structure. The various facial muscles attach onto the skull in different places depending on their function. These individual bones in adults are fused via ossification of the cartilage between bones that are found in young animals. The skull protects the brain and head against injury and supports the structures of the face. The neurocranium lies ventral to the brain and develops from the neural crest and mesoderm where it undergoes endochondral ossification. The dermatocranium lies dorsal to the brain and develops from the neural crest and mesoderm where it also undergoes intramembranous ossification. The viscerocranium constitutes the pharyngeal skeleton and is derived only from the neural crest and undergoes endochondral and intramembranous ossification. The classification of bones within the skull is based on the traditional views of skull drawings such as the historical drawing shown on the right.  

The skull is divided into three broad components - the neurocranium, the dermatocranium and the viscerocranium. The neurocranium lies ventral to the brain and develops from the neural crest and mesoderm where it undergoes endochondral ossification. The dermatocranium lies dorsal to the brain and develops from the neural crest and mesoderm where it also undergoes intramembranous ossification. The viscerocranium constitutes the pharyngeal skeleton and is derived only from the neural crest and undergoes endochondral and intramembranous ossification. The classification of bones within the skull is based on the traditional views of skull drawings such as the historical drawing shown on the right.  

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