374 Annals of the South African Museum. 



The occipital fragment consists of that portion of the skull which 

 lies between the two auditory notches and behind the parietal fora- 

 men. It includes both occipital condyles, the back part of the 

 parasphenoid (vomer), and the posterior portions of both pterygoids. 

 The occiput bears a very considerable resemblance to that of Cajnto- 

 saurus stantonensis, recently figured by Smith Woodward. The 

 basioccipital seems to be distinct from the exoccipitals, and to .be 

 a flat bone interposed between them and the back part of the para- 

 sphenoid. It probably forms the middle portion of the concave wall 

 between the condyles. The exoccipital, besides forming the condyle, 

 sends one process outwards and another upwards, a large oval space 

 lying between the processes. On the under and outer surface of 

 each condyle near its base is a small foramen for a nerve. By 

 comparison with the frog's skull we might readily conclude that 

 the foramen was for the vagus nerve, and Smith Woodward con- 

 cludes that a similar foramen in Capitosaums is for the vagus. But 

 while this may probably be the correct conclusion, it seems just 

 possible that the foramen may be for the Hypoglossal. It seems, 

 being only 1^ mm. in diameter, to be too small for the vagus of an 

 animal which probably was 10 feet long, and there seems to be a 

 larger foramen further back which may have been for the glosso- 

 pharyngeal and the vagus. In Ccqntosaiirus the supraoccipital is 

 cartilaginous, but here there is a well-ossiiied bone, and the exocci- 

 pitals seem to meet above the foramen magnum, and to shut out the 

 supraoccipital. Above the supraoccipital are the two membrane 

 bones usually called in error " supraoccipitals," but to which some 

 other name must be given. J^mith Woodward calls them svipra- 

 temporals, but as this name is largely used for one of the bones 

 of the temporal roof it seems better to give it a distinctive name. 

 Some time ago I suggested " postparietal." To the outer side of the 

 postparietals lie the bones usually called " epiotic," but which, being 

 pretty certainly membrane bones, should be called either supratem- 

 porals, as done by Smith Woodward, or post-temporals, as I have 

 suggested. The objection to Smith Woodward's term lies in the 

 fact that " supratemporal " is largely used as the name for one of 

 the temporal roof bones further forward, and it seems inadvisable to 

 use the same name for two or three different bones. Below this 

 lateral so-called post-temporal is a bone which appears distinct, and 

 which is probably, as believed by Smith Woodw^ard, the opisthotic. 

 It meets the lateral process of the exoccipital and, above the oval 

 vacuity, what I believe to be part of the supraoccipital. Lying a 

 little in front of the lower part of the opisthotic is the long rounded 



