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 felt. The high ridge which runs across the bone can be felt extending to the top of the shoulder.

The Pelvic Girdle.—The edges of the hip bones can be felt at the sides of the hips (Fig. 28). The hip bones, with the base of the spine, form a kind of basin called the pelvis.

The skull (Fig. 33) rocks, or nods, on the top vertebra. It consists of the cranium, or brain case, and the bones of the face. The shapes and names of the bones of the skull are shown in Fig. 33.

, disjointed.

Adaptations of the Skull for Protection.—Its arched form is best for resisting pressure and turning aside blows. Like all flat bones, the skull has a spongy layer of bone between the layers of compact bone forming the outer and inner surfaces; hence it is elastic and not easily cracked. The nose, brow, and cheek bones project around the eye for its protection. The delicate portions of the ear are embedded in the strongest portion of the skull. The branches of the nerves of smell end in the lining of the bony nasal chambers. The spinal cord rests securely in the spinal canal.

The arms and legs have bones that closely correspond to each other. The Latin names of these bones, as well as of all the other bones, are given in Fig. 28. There are 30 bones in each arm and 30 in each leg (Fig. 34). Here is a list of the bones of the arm, followed by the names in brackets of the corresponding leg bones: upper arm bone [thigh bone], 2 forearm bones [shin bone and