ON THE FAUNA AND #LORA OF THE TRIAS OF THE BRITISH ISLES. 305 
The accompanying illustration drawn to scale shows a portion of the 
track. The line marking the centre of the track not only touches the 
bases of the V. digit of the pes—the swollen one—but 
runs almost along the axes of I., the smallest digit. 3) 
The axis of each foot measured along the middle digit 
is turned outwards from the central line at about 30°, Ny 
so the animal walked with its feet splayed outwards to Saye 
each other at an angle of 60°, =e 
It will be noticed, too, that the weight mainly 
rested on the outer toes, for the inner ones are lightly 
impressed, while the outer ones are swollen and fleshy, 
and make deeper impressions. This would no doubt 
give greater stability to the animal on walking over mud ¥ 2 
or loose sand. The length of the stride is remarkably fi L 
uniform, only varying from 2 feet 74 inches to 2 feet 
8 inches. Sam 
The manus, on the other hand, is not so regularly 
disposed. The right manus in each case is from 
14 inch to 3 inches in advance of the pes, while the 
left is superimposed on the terminal phalange or nail ty 
of the pes. They all trend outwards, corresponding Se 
roughly with the direction of the pes. rm Wy 
Measurements of the pes show that the axes of the | : 
digits converge towards the base of the V. digit. NY 
Reckoning from this point, the length of the various 
digits are as follows: I., 5 inches ;-II., 6% inches ; 
III., 7 inches ; IV., 5,%; inches ; V., 33 inches. With 
the exception of V., which has two, the toes have 
three joints, with well-marked, fleshy pads, and at 
their bases other pads are seen which fuse together to 
form a continuous ridge. In these respects it is 
remarkably like the human hand, but there is no sign 
of the fleshy pad which joins the little finger with the 
wrist in the latter. 
Each toe is terminated by a claw, and this extends 
1333 40 J1V9S 
oc 
S&S 
beyond the limits of the digits to distances varying oes 
from half an inch to an inch. It would seem that the \N\ 
animal had the power of extending and retracting its tgs 
claws, for sometimes they appear as round or triangular wD 
punctures made by a pointed object, and at other times 
as long oval markings, such as would be made if the claw were extended 
The tubercles described by Mr. Beasley as occurring on the under-surface 
of the foot extend, not only over the fleshy pads, but also in the hollow or 
palmar surfaces. 
Details of the manus are not easy to determine owing to the smaller 
size and the very faint impressions left for examination. The second, 
third, and fourth fingers are always close together, while the first and the 
fifth usually appear as small indistinct markings, sometimes quite isolated 
from the others. In most cases they are absent altogether, and until the 
present exceptional find it was regarded as a three-fingered hand. In 
some slabs showing typical pes of this kind the manus is entirely 
wanting. This and other considerations lead one to surmise that the 
manus played a very subordinate part in progression. It may be that 
1907, Xx 
