1870. ] HULKE—KIMMERIDGE PLESIOSAURIAN REMAINS. 617 
bone is unusually thick, reaching 23 inches at the angle; and the arti- 
cular surface is correspondingly broad from the dorsal to the ventral 
margin. ‘he proximal end bears a subhemispherical articular head 
(figs. 1 & 2, a), the axis of which makes an angle with that of the 
cylindrical shaft. A groove passing between the pre- and postaxial 
borders separates this articular caput from a prominent, non-arti- 
cular, narrow, trochanteric upward production of the dorsal surface 
of the bone (fig. 2,6). The trochanter (mutilated in our specimen) 
descends a short distance along the postaxial border. The groove 
which separates this from the articular caput descends along both 
borders, on the postaxial one inclining to the ventral surface along 
the prolongation of the trochanter. A constriction below the articular 
head marks off on the ventral surface a smooth neck, beyond which 
the whole breadth of this surface and also the postaxial border of 
the cylindrical part of the humerus are occupied by a very rough 
and swollen muscular impression. The expanded distal part of this 
surface is smoother. From the preaxial border transversely, this 
surface is gently convex to the wing, where there is a shallow lon- 
gitudinal hollow. The dorsal surface is smoother than the ventral. 
A low eminence appears at about one-third of the length of the bone, 
measured from the upper edge of the trochanter. I am unable to 
select the other bones of this fore paddle. 
The femur (fig. 3) is rather longer than the humerus, and it is 
also less massive. This is particularly noticeable in the shaft. It 
has a subglobular articular head (figs. 3 & 4, a) placed obliquely on 
the shaft, separated, as in the humerus, by a groove from a very 
largely developed trochanter (fig. 3, e, & fig. 4, 6), which projects 
strongly postaxially, and descends on this border of the shaft. The 
groove also descends on both borders of the bone. It is deeper than 
the corresponding groove in the humerus. The articular caput is 
followed by a smooth constricted neck, to which succeeds, on the 
ventral surface and postaxial border a large rough warty swelling. 
The preaxial border (fig. 3, c) is concave, not straight as is that of 
the humerus; and the postaxial border (d) is still more concave, 
its distal half curving strongly backwards, and making an extremely 
large wing with the distal border. This last border is very remark- 
able: its outline consists of three distinct segments, corresponding 
to as many divisions of the distal articular surface, which is one in 
excess of those present in typical Plesiosauri. The preaxial and 
the next postaxial division of this surface meet in a large angle 
lying just behind the axis, as in the humerus. Behind this is a 
second postaxial division of the articular surface, answering to the 
wing. The greater part of this, the third division of the distal arti- 
cular end, is wanting ; but its form is perfectly given by that of the 
corresponding bone in the second segment of the paddle. 
This segment of the hind limb, the equivalent of the leg, contains 
in a transverse row three flattened angular bones of nearly equal size 
(f,9,h), each of which articulates proximally with one of the divisions 
of the distal articular surface of the femur, and distally with the 
members of the succeeding segment of the paddle. Laterally the 
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