INVESTIGATION OF FAUNA AND FLORA OF TRIAS OF BRITISH ISLES. 277 
strongly convex, as if the middle of the digits sank more deeply into the 
mud than their roots or terminations, the digits themselves being bent 
backwards. 
When the claws are bent sideways they frequently present a triangular 
impression, as if much compressed laterally ; there is, however, a possibility 
of this being the result of movement. 
A much larger print with quite the same character is occasionally 
found with the IV digit measuring over 6 cm. in length. It also shows 
the same lateral bend of the digits and claws. It is, however, not advis- 
able to separate it from the type just described, and it may be included 
under D1. The frequent absence of any trace of the V digit may either 
be caused by its being too short to touch the ground, or it may have been 
turned backwards and only occasionally have left traces of its presence. 
D 2. There is another form found frequently in the Runcorn district, 
and occasionally at Storeton and elsewhere, in which 
the digits are about the same length as in D 1, but 
are not half the thickness, and are more widely 
separated at the base. A small but typical example 
is in the Museum of the University of Liverpool, 
and was obtained by the late Dr. Ricketts from 
Daresbury. It shows the five toes, and a little in 
its rear there is the impression of the corresponding 
forefoot, or rather what we may suppose to be such, 
which agrees with it in form, but is somewhat less 
than one-half the size. In this example the digits 
D2. 2. 
at 
are quite straight, but they are often found bent, 
and with a sharp flexing of the joints of the 
phalanges which contrasts strongly with the more 
regular curvature of D 1 (pl. iv., fig. 1). 
The digits often have blunt, slightly thickened terminations, and no 
trace of a claw. This feature seems to occur 
very frequently in footprints, and it is uncertain D3. 4-—Left pes. 
whether it implies a difference in structure or 
is merely the result of a movement of the ex- 
tremity when the print was made. 
D 3. A third form, in some respects resem- 
bling these, has been found in South Staffordshire 
by Mr. Beeby Thompson in beds rather higher 
in the Lower Keuper than the footprint beds of 
Cheshire. It differs principally from D 1 in the 
form of the V digit. The first is also rather 
longer than in D 1 and 2. 
The prints are described and figured by Dr. 
A. 8. Woodward (‘Geol. Mag.,’ N.S., Decade 
IV., vol. ix., pp. 213-217, May 1902). He says: 
‘The total length of the fore-foot is 0:04 M., 
and the maximum breadth 0:025 M. As in 
the hind-foot, the terminal phalanges are very 
distinctly shown to have the form of sharp 
claws, and the V digit is slightly opposed to 
the remainder. The joints of digits I to III 
are well seen, and comprise respectively two, three, and four phalanges ; 
but digits I and V are unfortunately indistinct. 
