g8 
Annals of the Transvaal Museum 
The proximal articulation surface is roughly convex, with small concavities 
in its anterior portion. The lateral posterior side of the surface is lower than 
the medial posterior corner and this again 
is slightly lower than the anterior end. 
The hinder border is overhanging. The 
shape of the proximal articulation surface 
is given in text-fig. 6. The shaft narrows 
down quickly immediately below the 
head. The distal end is transversely 
broad. The medial one-third of the distal 
articulation surface is more or less flat 
and slopes very slightly from its anterior 
edge backwards and downwards. The 
anterior part of this surface is convex. 
The lateral part of the distal articulation 
surface consists of an anterior and a 
posterior portion. The anterior portion, 
which is the distal surface of the pro- 
cessus tibiae anterior distalis, occupies a 
much higher position than the posterior Text-fig. 6. Eucnemesaurus fortis. Left 
portion, which is the distal surface of the t‘ bia - Outline of proximal articula- 
r . , ,. . .. /-p.1 tion surface seen from above, 
processus tibiae posterior distalis. The Latera i side to the left, x J. 
distal surface of the processus posterior 
is continuous with the medial portion of the articulation surface. It slopes 
upwards from the lateral to the medial side and from the anterior towards 
the posterior border. As the processus 
posterior is rather weathered, especially 
laterally, the last fact might be due to 
this cause. If it is original, it would be 
a marked difference with the tibia of 
Dromicosaurus gracilis, where the sur- 
face slopes upwards from the posterior 
towafds the anterior border. The medial 
end of the distal surface of the processus 
anterior slopes down gradually towards 
the medial portion of the articulation 
surface, with which it j oins up by means 
of a broadly convex ridge. The distal 
face of the processus anterior slopes from 
its medial end upwards and outwards and from its anterior border backwards 
and slightly upwards. Medially the processus posterior is slightly broader than 
the processus anterior. It is bluntly pointed towards the lateral side. Laterally 
it is bent very slightly forwards. Both ends of the distal surface of the pro- 
cessus anterior are broad, but the inner end is slightly broader. The lateral 
end of the processus does not project further outwards than the processus 
posterior. The highest point of the lower surface of the processus anterior is 
situated 46 mm. above the lowest part of the processus posterior. The sulcus 
malleoli tibiae is very deep. This sulcus begins rather far above the processi 
and passes down between them towards the hinder border of the processus 
anterior. The greatest breadth of the distal end, parallel to the front border, 
is 14*5 cm. The front border is laterally slightly concave and medially convex. 
The medial border makes an acute angle with the anterior border and an 
obtuse angle with the posterior border. The anterior medial corner is globose; 
Text-fig. 7. Eucnemesaurus fortis. Left 
tibia. Outline of distal articulation 
surface seen from below. Lateral 
side to the left, x J. 
