The bones in animals are all connected with one single bone, and
are interconnected, like the veins, in one unbroken sequence; and
there is no instance of a bone standing apart by itself. In all
animals furnished with bones, the spine or backbone is the point of
origin for the entire osseous system. The spine is composed of
vertebrae, and it extends from the head down to the loins. The
vertebrae are all perforated, and, above, the bony portion of the head
is connected with the topmost vertebrae, and is designated the
'skull'. And the serrated lines on the skull are termed 'sutures'.