OF HYPSILOPHODON FOXII. 
1055 
ment of a fifth, probably also in the presence of two distinct tarsalia answering to 
those of the outer side in the distal row of tarsalia in higher Vertebrates, the hind foot 
of Hypsilophodon closely agrees with that of the Liassic Scelidosaurus Harrisonii. 
The sharp pointed curved ungual phalanges, of very different form to the blunt 
depressed unguals of Iguanodon Mantelli, are obviously related to a different habit 
of life. Hypsilophodon was adapted to climbing upon rocks and trees. 
Postscript. 
(Added October 9, 1882.) 
Since the above was written, further work by the skilful mason of the Palaeonto¬ 
logical Department, Mr. Barlow, upon a block of sandstone in the Fox Collection in 
the British Museum, has very recently brought into view several additional parts of 
the skeleton, of which the pelvis is represented by Plate 75. These afford much 
information respecting the structure of the fore limb, and an opportunity of com¬ 
paring the fore and the hind limbs in the same individual. In the left fore limb the 
coracoid and scapula remain naturally articulated, and the natural relations of the 
humerus, ulna and radius are only slightly disturbed, but the manus had broken up 
and its bones were scattered before the consolidation of the rock. The right ulna and 
radius with the manus attached, the dorsal surface towards the spectator, are well 
preserved. 
The shapes and proportions of the coracoid, scapula and humerus agree so nearly 
with those already given from other specimens as to make any detailed description of 
them superfluous—the chief apparent difference is the absence of the slight projection 
from the posterior border of the scapula shown in Plate 73. A textural difference in 
the fossil marks off the expanded vertebral end of the bone as a supra-scapula. The 
length of the scapula including its supra-scapular part is nearly 9'7 centims., and 
that of the humerus is 9 *5 centims. 
The fore-arm (Plate 79, fig. 3) is shorter than the arm. The length of the left 
ulna is 8*7 centims. (that of the right ulna 8‘5 centims,, the slight difference is 
explained by the different exposure of the proximal end); the radius is shorter, its 
length being 7*8 centims. (the right radius 7*7 centims.). 
The ulna is stout and massive at its articular ends; and its shaft is laterally so 
compressed as to greatly narrow the posterior surface in this part. The distal end of 
this bone, 1*3 centims. wide, appears to me to afford—relatively to the radius—a 
larger support to the carpus than the same bone in Iguanodon Mantelli. The radius 
is a more slender bone than the ulna and its figure is more cylindroid. Its proximal 
end is slightly expanded. The capitellum is followed by a slight contraction or neck 
MDCCCLXXXII. 6 T 
