The scapula (fig. 69, st) is a short and strong bone, its blade appearing as a short and narrow sub-compressed process extending from the subquadrate, thick and expanded end which affords the articular surfaces for the coracoid, clavicle, and humerus.
The clavicle, which is an exogenous process in Plesiosaurus, is here united by a strong oblique suture to the scapula. It expands into, or sends off from its outer part, a broad, flat, obtuse process, near the suture ; then contracts and bends inwards to the episternum, to which it is articulated also by suture.
The coracoid (fig. 69, 32) sends forward a broad and short flattened process, separated by a narrow notch from the scapular part of its head ; it then contracts and soon expands into a broad, flat, sub-triangular plate, the broad and straight border of which articulates with that of the opposite coracoid. A wide unossified interval separates the coracoid from the episternum. The ossification of the coracoid in the direction of this interval gives the peculiar longitudinal or fore-and-aft extent to those bones in the Plesiosaur, in which they unite with the episternum.
The pelvic arch presents a closer correspondence with that in the Plesiosaurus (fig. 71). The ischium (fig. 69, 63), con tracting beyond its articular head, there expands into a flat subtriangular plate. The pubis (fig. 69, 64) is a subcircular flat bone, with a notch near the articular end.
The bones of the limbs, although evidently those of fins or paddle-shaped extremities, are better developed than in Plesiosaurus, and more resemble the corresponding bones in the turtle (Chelones). The tuberosities or processes for muscu
lar attachment near the head of the humerus (omitted in the diagram) are better marked, especially that on the concave side of the shaft ; the distal end is thicker and less expanded. The whole bone is more curved than in any Plesiosauri. The femur (fig. 69, 63) is relatively longer and less expanded at its distal end. The bones of the fore arm, like those of the leg (ib. 66 and 67), are longer than in Plesiosaurus. The articular surfaces present the foramina with raised borders, which characterize those in Plesiosauri, and which indicate the fibro cartilaginous nature of the joints.
There is a ligamentous or unossified space at the back part of both carpus and tarsus (fig. 69, 68). At present there is evidence of but four digits in both the fore and hind paddles of Nothosaurus; the metapodial and phalangeal bones are of the elongate flattened simple form, characteristic of supports of a tegumentary fin.
One species of Nothosaurus (IV. Schimperi, Von. M.) is from the lower division of the trias, called " gres bizarre" of Soulz les-Bains ; the other representatives of the genus (N. giganteus, N. venustus, N. Miinsteri, N. Andriani, N. angustifrons, and N. mirabilis), are from the muschelkalk of Bayreuth and Luneville.