738 MR. D. M. 8. WATSON ON 
outside its articulation with the basisphenoid. This rises in the 
skull till its upper end nearly touches the parietal lateral to the 
parietal foramen. 
The general structure of the roof of the skull is already quite 
familiar from the figures and descriptions of Seeley, Smith 
Woodward, and Broom. The figures in this paper will, I hope, 
explain any doubtful points: the relations in important regions 
are described below. 
The quadrate is a comparatively small bone; it has a small 
condyle for the mandible, above which it rises vertically. The 
body of the bone is in contact with the very large and massive 
quadratojugal at its lateral border; it is then separated from 
this bone by the quadrate foramen. Above this level the whole 
posterior surface of the quadrate is covered by the squamosal. 
The quadrate sends a long process inwards which is covered 
posteriorly by the posterior ramus of the pterygoid. 
The squamosal isa bone of medium size which may be described 
as consisting of three parts. The posterior and largest of these 
covers much of the back of the quadrate; it curves round to 
form the second region, which lies entirely on the outer side of 
the skull, having sutures with the quadratojugal, jugal, post- 
orbital, and tabulare. The third part arises from the other two 
and passes inwards and backwards over the otic notch to nearly 
or quite touch the parietal. The whole of this part is covered by 
the tabulare. 
The tabulare is a very large bone forming the posterior corner 
of the flat upper surface of the skull. Its anterior end overlaps 
the parietal and squamosal to a very large extent, but its hinder 
margin is free, and is deflected to meet the upper posterior corner 
of the paroccipital. 
Of postparietals there is usually no trace, but in the skull of 
the female skeleton, which is well preserved, there are quite 
clearly a pair of small bones articulating with the pointed mesial 
posterior ends of the parietals. These are very small, only about 
1 millimetre square, but can only be interpreted as vestigial post- 
parietals. They stand out quite freely and touch no underlying 
bones. 
An interesting point is that the nasal cavity is very largely 
separated from the very large orbit by plates arising’ from the 
lachrymal and prefrontal. 
The septomaxilla is a small bone articulating with the pre- 
maxilla and nasal and forming the posterior border of the nostril. 
‘The material at my disposal has shown no trace of a para- 
sphenoid, but Dr. Broom has recorded it in an Albany Museum 
specimen. 
A curious feature of the very well-preserved skull of the male 
skeleton is the presence of a small depression with rather stee 
walls on the outer surface of the maxillaand nasal, just behind the 
upper end of the septomaxilla. This prabably lodged a superior 
labial gland. 
