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the parietal foramen or foramina are located, and Wormian bones of
large size are often found within the suture.
II. The Fronto-parietal or Coronal t'^uture is between the frontal and
parietal bones, extending across the anterior portion of the cranial vault
from the superior extremity of the great wing of the sphenoid bone on
one side to the same point on the other.
III. The Occipito-parietal or Lmnbdoid Suture is between the occipital
and parietal bones, extending from the mastoid portion of the temporal
bone on one side upward to the interparietal suture, and thence down-
ward to the mastt)id portion of the temporal bone of the other. Wor-
mian bones are more numerous within this than the other sutures.
The Sutures of the Lateral Portions of the Cranial
Vault are six in number, without referring to the parieto-li'ontal
and the parieto-occipital articulation where they come within these
regions.
The Fronto-malar tSuture, describing this region from its anterior to
its posterior boundary, is lietween the external angular process of the
frontal bone and the frontal j^rocess of the malar bone.
The Fronto-splienoklcd Suture is within the temporal fossa, where the
frontal bone articulates with the great wing of the sphenoid bone. This
articulation forms the second suture.
The Spheno-maJar Suture is the third it also is within the temporal
;
fossa, and is formed by articulation of the malar bone with the anterior
border of the great wing of the sphenoid bone.
The Farieto-sphenoid is the fourth, and is found between the parietal
bone and the tip of the great wing of the sphenoid bone. In some rare
cases the parietal bone does not articulate with the sphenoid at this
point ; the frontal bone then articulates directly with the squamous por-
tion of the temporal bone.
The Farieto-squamous Suture, the fifth, is formed by the articula-
tion of the parietal bone with the squamous portion of the temporal
bone.
The Farieto-mastoid Sidure is the sixth, and is formed by the artic-
ulation of the parietal bone with the mastoid portion of the temporal
bone.
The Sutures of the Face.—In the face the frontal bone assists
in forming several sutures. These likewise receive their names from
the bones that form them, as the fronto-sphenoid, fronto-ethmoid, fronto-
lachrymal, fronto-maxillary, and fronto-nasal. This rule for naming
sutures is carried out in describing the articulations betw^een the other
bones of the face.
The Articulations of the Occiput are those between the occipital
bone and the posterior inferior angle of the parietal bone, and of the
occipital bone and mastoid portion of the temporal bone.
The articulations between the bones at the base of the brain-case are
the occipito-sphenoid, occipito-temporal, and the temporo-sphenoid. In
early life a thin layer of cartilage is inter})osed between these bones,
which at adult age becomes ossified. These articulations, therefore, are
of the synchondroidal variety.