38 
FOSSIL REPTILIA OF THE 
the metacarpus is 5 inches in the left hand, and but 4^ inches in the right, both being 
preserved in their natural connections as they were buried, but one showing a more 
expanded, the other a more contracted, condition of the fin. 
The first metacarpal (Tab. XIV, fig. 2, i) is 1 inch 9 lines in length, and supports 
two phalanges ; the total length of that digit, including the metacarpal, being 4 inches 
3 lines. The second metacarpal (ib., ii) is 2 inches 3 lines in length ; it supports five 
phalanges ; the total length of the digit, including the metacarpal, is 9 lines. The 
third metacarpal (ib.,iii) is 2 inches 8 lines in length; it supports five phalanges; the 
total length of the digit, including the metacarpal, is 9 inches 9 lines. The fourth 
metacarpal (ib., iv) is 2 inches 5 lines in length ; it supports four phalanges, and is the 
same length with the preceding. The fifth metacarpal (ib., v) is 3 inches 3 lines in 
length, with its ulnar margin more deeply concave than in the others ; it supports four 
phalanges, most of which show the same deeper concavity, with a greater production 
of the ulnar ends of the articular expansions ; the total length of this digit is 8 inches 
6 lines ; a distal phalanx is wanting in it, and the same may likewise be the case with 
the others. 
There is a want of precise symmetry in the proportions of the right and left fore 
paddles, those of the right being longer and somewhat slenderer than those of the left. 
The whole of the outer surface of the carpal bones is rugose, as is the chief part of 
that of the metacarpals and phalanges. The total length of the bones of the right 
pectoral limb, as here preserved, is 2 feet 3 inches ; the breadth of the antibrachium is 
6 inches 6 lines ; that of the carpus 6 inches ; that of the metacarpus 5 inches ; the 
interspace between the heads of the two humeri is 1 foot 6 lines. 
Pelvic arch and limbs (ib.). 
The iliac bones (Tab. XIV, fig. 1, 62), dislocated by pressure, lie in the axis of the 
trunk, parallel with the ischia (ib., 63) ; the vertebral end of the ilium is broader but less 
thick than the acetabular one; the length of the bone is 4 inches 10 lines, the breadth 
of the vertebral end is 3 inches 6 lines ; the breadth of the acetabular end is 2 inches. 
The surface here exposed, probably the outer or posterior one, shows a slight concavity 
on the vertebral expansion, where the bone is smooth ; beyond, it becomes longitudinally 
striate, and rugose or tuberculate near the acetabular extremity ; this is thickened and 
obscurely divided into the rough synchondrosal surface for the ischium, and the cor- 
responding somewhat smaller surface for the ligamentous attachment of the femur. 
The ischium (ib., 63) is flat, and of the usual elongate, triangular form ; it joins its 
fellow by its straight inner side having the posterior angle rounded olf ; the outer, 
obtuse, non-articular border presents a sigmoid curve, concave near the ilium. The 
anterior shorter border is emarginate in the middle, where it forms the posterior 
boundary of the obturator foramen (ib., o), the straight articular parts of this side 
