Contributions to South. African Vertebrate PaUconiohMjij. 1. 189 



and the upper end is not nearly so expanded. On the posterior edge 

 there is a similar muscular impression above the glenoid cavity. 

 The coracoid of Bclodon differs from this one in having the foramen 

 formed partly by the scapula. In size and shape there is, however, 

 a slight similarity between the genera. In ErytJirosuchus the bone 

 is, as is the case with the other bones which we can compare, very 

 much more heavily built. In Herpetosuclius the coracoid and 

 scapula bear a slight resemblance to those of ErythrosucJius. In 

 Stagonolepis the resemblance is apparently considerable. The 

 coracoid foramen is entirely in the bone, and the general shape 

 is like that of Erijthrosuchus. The scapula of Stagonolcjjis has also 

 a fair resemblance to that of the South African genus, though it is 

 apparently more slender. In both forms the coracoid is sometimes 

 found anchylosed to the scapula, but in Erythrosuchus the coracoid 

 shows no evidence of anchylosis, being indeed somewdiat displaced 

 from its true position. 



Humerus. 



The right humerus has been preserved in almost perfect condition. 

 It is extremely massive, and at first sight recalls the humeri of the 

 Anomodonts or of Pareiasaurus, but careful examination shows this 

 resemblance to be only superficial. When view^ed from the front 

 the bone is dumb-bell shaped, with the proximal and distal ends 

 greatly expanded, and the middle portion slender. The proximal 

 end is moderately flat in the centre, but curves slightly downwards 

 at the outer and inner ends. It is about 50 mm. thick throughout, 

 and has a well-marked groove along its entire length : the surface is 

 very irregular, and there can be little doubt that there was on the 

 end of the bone a pad of cartilage probably 30-40 mm. in thickness. 

 The main axis of the proximal end makes with the main axis of the 

 distal an angle of about 30°. The width of the upper end is 230 mm. 

 From its outer end and almost at right angles to it there passes for- 

 ward a thick, well-developed, delto -pectoral ridge. This is continued 

 downwards to about the middle of the bone, where it ends abruptly 

 almost exactly as in Dicynodon. In its upper part the ridge is 

 71 mm. thick, but it gradually thins down, and ends in a moderately 

 sharp edge. The anterior surface of the delto-pectoral ridge is fairly 

 smooth and rounded. In front a deep hollow is formed between the 

 ridge and the main part of the humerus. The narrow part of the 

 shaft is 77 mm. wide and 18 mm. thick. There is no trace of either 

 an eiido- or ecto-condylar foramen. The narrow middle portion 

 rapidly widens to the distal end, and here again there must have 



