Note S — Chapter IV

"The sauroid or lizard-like fishes," says Dr. Buckland, "combine in the structure, both of the bones and some of the soft parts, characters which are common to the class of reptiles. The bones of the skull are united by closer sutures than those of common fishes. The vertebræ articulate with the spinous processes of sutures, like the vertebræ of saurians; the ribs also articulate with the extremities of the spinous process. The caudal vertebræ have distinct chevron bones, and the general condition of the skeleton is stronger and more solid than in other fishes: the air bladder also is bifid and cellular, approaching to the character of lungs; and in the throat there is a glottis, as in sirens and salamanders, and many saurians."—Note to Bridgewater Treatise, p. 274, first edit.