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    The trapezoid is a smaller bone than the preceeding and has like the pisiform bone its great diameter from side to side. It presents an articular edge to the unciformis.
    The unciform bone is of the same size and shape as the last and therefore needs no further notice.

    THE META-CARPUS.    The meta-carpus consists of five bones, which have a long axis from above to below, and an inferior articular extremity and a narrow body.

    THE PHALANGES.    These are much like the meta-carpal bones in form, and need no further comment save that their superior or meta-carpal extremity is larger than the inferior one. They amount to twenty-seven and are thus situated :

    All the bones of the paddle had inter-articular cartilages, they diminish in size towards their extremity and grow wider apart.

THE POSTERIOR EXTREMITIES.

     The posterior extremities, which are longer than the anterior, are composed of the femur, leg and paddle.

     THE FEMUR.     The Femur (j) as a matter of course is somewhat like the humerus, but is longer, rounder and more slender. Its head which articulates in the cotyloid cavity is as much marked with fossæ as that of the humerus and has like it a rim for the capsular ligament. The body is rounded and smooth and spreads into the flattened surface of the inferior extremity of this bone. It is convex below and marked with striæ from above to without and beneath. Of the two external edges the posterior one is the most concavely curved.
    Connexion.    Superiorly with the ilii. ischii and pubes ; inferiorly with the fibula and tibia. The femur drawn in plate twenty-six was common with the other bones there to one individual.

     THE LEG. The fibula and tibia constitute this division. The fibula (k) the most external bone of the two has an upper anteriior and posterior flattened surface, a superior and an inferior articulatory extremity, an internal convex and rounded boundary and an internal semi-lunated edge.
    Connexion. Above with the humerus and below with the middle bone of the tarsus.
    The tibia (l) has, like the fibula, a semi-lunar border; it articulate with the femur and below with a vast inter-articular cartilaginous mass between it and the meta-tarsal bones.

THE POSTERIOR PADDLE.

     THE TARSUS.    Three bones constitute the tarsus - an external articular one, a median cuneiform bone larger than the preceding, and a third situated between them inferiorly. As may have been expected, these three bones have their anterior and posterior surfaces flattened and smooth like those of the carpus.
    THE META-TARSUS.    The five bones which compose the meta-tarsus have an upper and an interior articular surface, a narrow body and a long axis from above to below.
    THE PHALANGES.    The phalangal bones approximate in shape so much to those of the anterior paddle (as do indeed all the other bones of this division,) that we have only left us to mention their number and position, in order to terminate our anatomical description of the Plesiosaurus Triatarsostinus.