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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., n) 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.,m) 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 

 (3 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 

 G 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 off ; 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., °), the straight articular parts of this side 



