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Annals of the South African Muse Km. 



homologous with the mammalian interparietal, and therefore rightly 

 named. It articulates with the whole of the posterior end of the 

 parietals, and even extending beyond them supports part of the 

 squamosal. 



The squamosal is by far the largest bone in the skull. The pos- 

 terior part articulates with the exoccipital and supraoccipital, and is 

 also supported by the interparietal. The downward portion which 

 is supported by the exoccipital has attached to its lower end the 

 quadrate, and to the front of the plate the large quadrato-jugal. 

 The upper and inner portion of the squamosal passes inwards and 

 forwards as a narrow plate which rests on the interparietal and 

 on the parietal, and its most anterior part is covered by the post- 

 orbital. The zygomatic portion passes directly outwards from near 

 the top of the main portion of the bone, and then curves forwards 



FIG. 5. Occiput of Oudcnodon knlbei. About J nat. size. 



and ends in a point below the orbit. The greater part of the zygo- 

 matic process rests on the jugal, and the extreme anterior end is 

 in contact with the posterior part of the maxilla. 



The question of whether the Anomodonts have or have not a 

 quadrato-jugal is one which has occupied my attention for the last 

 ten years, and every skull with the articular region at all well pre- 

 served has been most carefully examined for further light on the 

 matter. The large flat plate which rests on the front of the lower 

 part of the squamosal has the appearance of a membrane bone, 

 and had any suture been found between it and the articular head it 

 would at once have been determined as a quadrato-jugal ; but in the 

 most perfect specimens hitherto examined it was quite clearly made 

 out that the articular end was the same bone as the flat ascending- 

 plate, and the whole was thus believed to be quadrate. Further, 

 there quite certainly was no quadrato-jugal bone in the Cynodonts, 

 and none seemed to be present in the Therocephalians ; it was thus 



