any one of the collagenous fibers of different thicknesses that cause the periosteum to adhere firmly to bones. Sharpey’s fibers pass at different angles from the inner layer of the periosteum and at different depths to the layer of the external general lamellae of the diaphysis of tubular bones. They become branched mainly in this layer, sometimes reaching the osteon layer but never penetrating the substance of the osteon lamellae. They can be readily distinguished on histological sections of growing bones. They become partly or completely calcified and almost invisible in the bones of persons of advanced age. Sharpey’s fibers were described by the British scientist W. Sharpey (1802–80).