_Description._—The hyoid bone consists of the following parts: the _body_, or _basi-hyal_, which is subcylindrical and presents in front a trochlear articular surface, convex transversely, and concave vertically for articulation with the ewer-shaped portion of the glosso-hyal. The anterior free portion, or lingual process, is called the _glosso-hyal_, or _entoglossal bone_. The lingual process gives support to the muscular and fibrous structures of the tongue. On either side of the basi-hyal there is a limb passing posteriorly along the side of the superior larynx, extending upward along the outer border of the occipital bone. This is the _cornu_ of the os hyoideum and is divided into two elements, first, the _basi-branchial_ which is bone and articulates with the basi-hyal, and the second, the _cerato-branchial_, cartilaginous in structure. In the center and projecting backward from the body of the os hyoideum is a spur process called the _uro-hyal_, partly bony and partly cartilaginous, and which rests upon the superior larynx. THE VERTEBRAL COLUMN The vertebral, or spinal column consists of 42 bones, as shown in the following table: Cervical region 14 Dorsal region 7 Lumbo-sacral region 14 Coccygeal region 7 —— Total 42 Many of the bones of the dorsal and lumbo-sacral regions do not have free articulations. The cervical and coccygeal alone have free movements. =The Cervical Vertebræ= (Fig. 4, No. 59; Fig. 5, Part II, No. 2). _Location._—The cervical vertebræ form the neck of the fowl. [Illustration: FIG. 9.—Os hyoidum and tongue muscles. 1, Glosso-hyal. 3, Basi-hyal. 4, Basi-branchial element of the cornua. 5, Cerato-branchial element of the cornua. 6, Uro-hyal or spur process. 7, Genio-hyoideus. 8, Cerato-hyoideus showing the slender tendon. 9, Hyoideus transversus. 10, Hyoideus transversus. ] _Description._—The long cervical section of the spinal column is S-shaped and is made up of fourteen vertebræ. The anterior segments move freely forward, the middle ones backward and the posterior ones forward, allowing the S-shaped curve of the neck. The neck is flexible so that it is possible for the beak to reach the coccygeal oil gland. The bird is enabled to reach the feathers on all parts of the body to cleanse and oil them. =The Atlas.= _Location._—The first cervical vertebra is called the atlas. Anteriorly it articulates with the single condyle of the occipital bone. Posteriorly it articulates with the axis, or second cervical vertebra.