The arterial system of a one-year-old infant was injected with red acrylic plastic following which the soft tissues were corroded with potassium hydroxide. The specimen has been prepared to illustrate the arteries of the vertebral column and the relation of these vessels to the posterior portions of the ribs. Ossification of the vertebral bodies and neutral arches is incomplete. This preparation was made by Dr. Donald L. Stilwell, who kindly granted permission for those photographs to be recorded. The present view and the succeeding ones of this series illustrate various aspects of the vessels that supply the vertebral column.