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1. Skull, or skeleton of the head, the most anterior (forward) part of the horse’s skeleton, articulates with the first cervical vertebra (or atlas), from which it is suspended by its posterior (or back part) extremity, its anterior (forward) extremity being free. Its position varies with the attitude of the animal; but in our descriptions we shall always suppose it to be placed in a horizontal position.

In the young animal the skull is composed of a number of bones, all of which, with the exception of the lower jaw, the teeth, the bones of the tongue, and ossicles of the ear, become united by ossification (growing together) in the adult.

In speaking of the different points of importance in connection with the head bones of the horse, and other animals, suppose a cross or longitudinal section of the head is made. It will be noticed that it is full of cavities or sinuses. The uses of these are to lighten the head and also to warm the air as it passes into the nostrils, on its way down to the lungs. It will also be found full of foramen or small holes through which the nerves from the brain and various blood vessels pass to the organs situated in the head, such as the tongue, lips and the various glands in and around the head.