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bits a plate bent towards the fibula, and its narrowest transverse 
diameter is two and a half inches. 
The portion of the fibula is eleven and.a half haere long. In the 
middle it is flat on one side, slightly concave on another, and convex 
on the two remaining sides. It presents the same cancellous struc- 
ture as the tibia, but the concentric arrangement of the layers of 
cells is more exact. ‘Towards the opposite end of the bone the con- 
cave side becomes first flat and is then pruduced into a convex wall, 
terminating one end of a transverse section of a compressed and bent 
thick plate of bone. 
Metatarsals.—These bones, Mr. Owen says, exhibit. the charac- 
teristic irregularity of length of the crocodilian metatarsals., Of two 
imbedded in the rock, and considered by the author to be the mner- 
most and second, the former or smaller measured one foot in length, 
and the latter two feet, having a diameter of eight inches at its 
greater and of four inches five lines at its narrowest or middle part, 
and of six inches at its other extremity, which was imperfect. ‘lhe 
whole of the bone within the compact outer crust consisted of cells 
varying from a half to two-thirds of a line in diameter. Portions of 
four other detached metatarsals are described. 
Ilia, Ischia, Pubis, and Coracoid Bone.—These bones, the author 
states, also conform to the crocodilian type. ‘The remains of the 
ilia are flat and nearly straight, and they gradually but. slightly 
widen towards one end. Of one ilium, a portion, twenty-five inches 
long and ten inches across at the broadest end, is preserved, and of 
the other a fragment twenty inches in length. 
The mesial extremities of the pubis and ischium are preserved in 
the same block of stone. ‘The pubis, Mr. Owen states, differs from 
the crocodilian type in its greater breadth. ‘The portion exposed 
im this block is principally convex, but it becomes concave towards 
the opposite or median margin. At its broadest part it is thirteen 
- imches across, and its length is seventeen inches. This expanded 
extremity is rounded, and the diameter of the corresponding ex- 
panded extremity of the ischium, which is obliquely truncated, is 
nine inches. In another block of stone the expanded extremity of 
the opposite pubis is preserved, and measures fourteen inches across 
and twenty-two inches in length. 
The bone, considered by Mr. Owen to be a coracoid, is two feet 
in length and seventeen inches in its greatest breadth, and it varies 
in thickness from three to five inches. ‘The breadth of this bone in- 
dicates, the author states, the great development of the muscles de- 
stined for the movement of the fore-leg, whence he infers that the 
anterior extremities were more powerfully and habitually used in 
progressive motion than in the Crocodiles, and that they were con- 
sequently provided with a webbed modification of the hand. 
Mr. Owen then enters upon the question of the identity or affini- 
_ ties of the Hythe remains with any of the known marine genera of 
the saurian order, the texture of the long bones being conclusive 
against their having belonged to the terrestrial genera, the Iguano- 
don and Megalosaurus. 
