Annals of the Transvaal Museum 107 
This half circle and the front border lie in a plane which makes an acute 
angle with the anterior surface of the pubic plate. 
Nothing is present of the bent-down portion at the inner proximal corner 
of the pubic plate. A broken edge indicates how far this bent-down portion 
continued towards the proximal end. From here 
the pubic neck continues towards thearticulatio 
ileo-pubica. The section of the neck is triangular 
as shown in text-fig. 2. The lateral border of the 
neck is a continuation of the lateral border of 
the plate, it is only slightly concave forwards. 
The hinder-outer surface of the neck is slightly 
convex. The neck has an anterior surface and 
an inner surface, which stand at right angles to Text-fig. 12. Dvomicosaurus 
each other. The anterior surface rounds off gracilis. Outline of distal 
broadly into the inner surface. Both surfaces are surface of pubis seen from 
concave from above downwards. The distance 
between the lateral border and the inner posterior border of the neck is 4 cm . 
The upper anterior corner of the bone and the articulatio ileo-pubica are 
weathered away. The thickness of the head at the upper anterior end is 
about 5 cm. The processus subacetabularis is not only bent downwards at 
right angles to the neck, but its general direction is also practically perpen- 
dicular to the pubic plate. The medial border of its upper surface is fairly 
straight. The proximal portion of this upper surface has a high boss on its 
lateral border. The distal portion shows a deep concavity, which does not 
affect the medial border, but which continues over the lateral border. The 
medial surface of the processus is concave in all directions and strongly so 
from above downwards. Its general section is triangular. The length of the 
processus is about 7-5 cm. The breadth of its upper surface is less than 
4-5 cm. The distal end of the processus subacetabularis is fiat and has a 
process which is directed downwards, forwards and inwards. This process 
stands practically at right angles to the processus subacetabularis. Distally 
it turns more and more inwards; its section is triangular. The lower end of 
the hinder surface of this process is damaged. The upper border of the 
triangular articulatio ischio-pubica, which is covered with small knobs and 
pits, has a breadth of about 4-5 cm. Its height as far as preserved is about 
the same. The breadth of the foramen obturatorium is 17 mm. Its length 
was more than 3 cm. 
Ischium. 
Both ischia are present, but they are very much broken. The left ischium 
is fairly complete, but it is broken in two and the parts are joined by a thick 
band of matrix. The thin upper anterior portion is badly broken and the 
extreme distal end is lost. The distal end of the right ischium is complete, 
but its proximal end is lost (PI. XV, fig. 4). 
If the bones are combined, it will be found that the length of the ischium 
is 34 cm. The distal portion is straight and the proximal plate is turned 
slightly outwards. The breadth of the proximal plate with the processus 
subacetabularis (PL XV, fig. 6) is 11 cm. A small piece of the posterior portion 
of the proximal end is broken off and the bone has suffered somewhat from 
pressure. The original total breadth may therefore have been 12 cm. The 
posterior portion of the proximal surface has a breadth of 6*5 cm. as pre- 
served. However, from this must be deducted 1 cm. for a seam of matrix, 
which passes in a sagittal direction through the posterior portion of the upper 
