On the Reptilian Genera Euparheria Broom, and Mesosvchus Watson. 87 
uncovered by bone in the centre of the pelvic basin. The pubis has one 
pubic foramen. The bending of the bone is greater than in Hoivesia and 
equal to that of Euparlceria. 
The femur is a short stout bone 50 mm. long, very different from that of 
Euparlceria. It is bent in a slight double curve. The head must have been 
cartilaginous, as the proximal end of the bone is excavate and finely rugose, 
approximating in shape to that of Howesia. There was a strong high 
trochanter at the proximal fifth of the bone. The bone differs from the 
femur of Howesia in being less expanded at the distal end and in having a 
stronger curve. 
The tibia is 49 mm. long, the fibula 45 mm. The proximal surface of 
the tibia has a maximum width of 12 mm., the shaft being 5 mm. thick. 
The fibula is a much more slender bone with a somewhat expanded distal 
end. 
The tarsus of the right side is seen from the plantar side, and is slightly 
displaced. In the proximal series there are three bones. A large bone, 
obviously formed by the fusion of two, lies directly opposite the distal ends 
of the lower bones of the leg. It is 14 mm. at its widest and has a maximum 
length of 7 mm. Lateral to it and apparently lying partly above it is a 
bone which has only a small triangular plantar face. External to this and 
partly articulating with the first is another large bone whose inner edge is 
raised and whose under-surface is saddle-shaped. The dimensions of this 
bone are 11 mm. by 8 mm. In the distal row four tarsalia are seen, of 
which the fourth is the largest. The metatarsals are not fully displayed, 
with the exception of the first and fifth. The first is a short stout bone ; 
the fifth is remarkably similar to that of Hoivesia. The digital formula is 
not obtainable. 
There can be little doubt that in the structure of the girdles and limbs 
Mesosuchus and Howesia are closely allied forms. The pelvis is very 
similar in the two genera and so is the general form of the limb-bones, 
while the similarity in the fifth metatarsal is very striking. The manus is 
not known in Hoivesia, and its interpretation in Mesosuchus is not beyond 
doubt. Much of the carpus was undoubtedly cartilaginous. There were 
certainly four distal carpalia. I have interpreted the other two bones as 
radiaie and ulnare ; the absence of a bony intermedium is strange, but there 
is room for it between the two proximal bones of the carpus. There were 
almost certainly cartilaginous centralia, and the lateral surface of the 
supposed ulnare is excavate as if for articulation with a cartilaginous pisi- 
forme. The digital formula of the hand is primitive. 
The structure of the tarsus is fairly clear, although the whole foot has 
been turned at an angle to the leg. The large bone which articulates with 
the tibia and fibula is taken to be a fused centrale and tibiale ; lateral to this 
and just possibly fused with it (although a suture seems undoubted on the 
