Hooper, Robert [Hrsg.]: The Anatomist's Vade-Mecum: Containing The Anatomy, Physiology, Morbid Appearances, &c. Of The Human Body ; The Art of making Anatomical Preparations, &c. To which are added Anatomical, Physiological, Medical, And Surgical Examinations For Students (London, 1811)

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The use of these bones is, to form the superior part of the
cranium.

The parietal bone, at birth, consists of one portion, and
partakes of the shape of the adult bone. It shews, very
beautifully, the radiated bony fibres, and the centre of
ossification.

The situation of the parietal foramen should not be
forgotten ; for when the artery which passes through
it is divided, it sometimes bleeds very profusely,
and being embedded, and somewhat retracted in
the foramen, caunot be secured by a ligature. In-
stances, it is said, have occurred, where blood has
collected from this cause between the dura mater and
cranium.

A considerable fossa is sometimes found in the internal
surface of these bones, near the longitudinal sinus ;
it is in consequence of the pressure of a protruding por-
tion of the sinus, or of the external Pacchionian glands,
by which absorption of the bone takes place.

The connexion of the parietal bones with the frontal, is
well worthy of attention. In the middle of the coronal
suture, where the os frontis, from its size and flatness,

« is the mMii in danger of being injured, it rests upon the
arch formed by the parietal bones; whereas at the
sides the parietal bones rest upon the os frontis, be-
cause the same arch is there in the greatest danger
from pressure.

OS OCCIPITIS.

Os basilare. Os memorial. Os nervosum.

The occipital bone is situated in the posterior part of the
head, and is somewhat of a quadrate oblong shape. The ex-
ternal surface of the occipital bone is convex, and very irre-
gular, serving for the attachment of several muscles ; the in-
ferior portion of the bone is stretched forwards like a wedge,
and at the base of this projecting portion are two condyles,