EXPLANATION

OF

PLATE V.

OF THE ETCHINGS OF THE SKULLS.

BEFORE entering on the consideration of the forms of the head, the reader may direct his attention to Plate V. I shall shortly point out the most remarkable bones and processes as they regard our present inquiry.

Fig. 1. The Skull of a Man fully grown, presented in a front

view.

A. The FRONTAL BONE (os frontis).

B. The PROTUBERANCES FORMED BY THE FRONTAL SINUSES,

(see the section of these cavities in fig. 4).

c. The TEMPORAL RIDGE OF THE FRONTAL BONE; on which the form of the temple depends.

D. The CHEEK BONE (or os malæ).

E. E. The UPPER MAXILLARY BONES.

F. The NASAL BONES.

G. G. The ORBITS OR SOCKETS FOR THE EYE BALLS. The circle of their margin is seen to be formed of the frontal bones, the cheek bones, and the superior maxillary bones.

H. H. The TEMPORAL BONES. These hollows are filled with a strong fleshy muscle, which arising upon the side of the skull, passes down through the arch to be inserted into the lower jaw-bone.

1. I. The MASTOID OR MAMILLARY PROCESSES of the TEMPORAL BONE. These are the points, into which the strong mastoid muscles which give form to the neck, are inserted.

K. The Lower Jaw.

L. The ANGle of the Lower Jaw.

M. The PROCESSES OF THE JAWS which form the sockets for receiving the roots of the teeth.

Fig. 2. Is the Skull of an Adult seen in Profile, in which we have to remark these parts:

A. The FRONTAL BONE.

B. The TEMPORAL BONE.

The ZYGOMATIC PROCESS OF THE TEMPORAL BONE, which,

with the process of the cheek bone, forms an arch, under which the tendon of the temporal muscle passes, to be inserted into the lower jaw.