Fauna and Stratigraphy of the Slormberg Series. 355 



is 14 mm. The length of the postglenoid process is 45 mm. while 

 that of the interclavicular articular surface is 37 mm. 



This coracoid differs from that of any known forms. In the Phyto- 

 sauria the coracoid is rounded in form and lias a large coracoid 

 notch, and the pre-glenoid portion is much longer than the post- 

 glenoid. In the Pseudosuchia the form is variable. Ornithosmhus 

 has a rounded coracoid with a short posterior ventral process, and 

 a supracoracoid foramen. Euparkeria has a large rounded coracoid. 

 Schleromochlus has a long, flattened, rod-like coracoid like those of 

 the Birds and Pterosauria. In the Crocodilia the coracoid approxi- 

 mates somewhat to that of Sphenosuchus. It also is composed of two 

 expanded ends joined by a relatively narrow neck. But in the 

 Crocodilia the bone is much higher and relatively shorter, and there 

 is a foramen instead of a coracoid notch. This latter feature, however, 

 is variable in the Crocodilia; for Andrews has figured two species of 

 Metriorhynchus from the Oxford Clay, one of which has a coracoid 

 notch and the other a coracoid foramen. In none of the Triassic 

 Coelurosauria is the coracoid known ; but in Aetonyx and other 

 Triassic Saurischia it is a large rounded bone with a supracoracoid 

 foramen, somewhat similar to that of Euparkeria. The South African 

 form which most closely approximates to Sphenosuchns in this respect 

 is Notochampsa. 



Humerus. The humerus is 113 mm. long. The proximal end is 

 broad ; in the inner view it is seen to be hollowed out between 

 the delto-pectoral crest and a well-marked ridge which runs down 

 on the inner side from the proximal condyle. The delto-pectoral 

 crest lies considerably below the level of the head of the bone, so 

 that the proximal expanded portion occupies two-fifths of the total 

 length. The shaft is slightly curved, and oval in cross-section, the 

 distal end being more strongly bent than the proximal. In the 

 narrowest part the shaft has a diameter of 10 mm. The distal end 

 is but slightly expanded and shows two distinct rounded condyles, 

 of which the inner is much the larger. Seen in lateral aspect, the 

 bone presents somewhat the appearance of that of Ornithosuchus, 

 but it is longer, more slender, and the distal condyles are more 

 rounded. 



Tibia and Fibula. There is also preserved a tibia and the distal 

 third of a fibula from the same limb. The tibia is a long, thin 

 bone slightly curved, with an expanded proximal end, and a robust 

 distal end. Its greatest length is 120 mm. ; the distal end is 15 mm. 

 wide, the shaft 9 mm., and the proximal end 29 mm. The tubero- 

 sitas tibiae is the highest point of the bone. From it the articular 



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