20 Transactions of the Boyal Society of South Africa. 
must thus regard all the specimens grouped under the name Galesaurus 
as belonging to two genera. The original form is a fiat-headed animal, 
with apparently a dental formula of ^'f, c\, m . All the other speci- 
mens, which must take the name Nythosaurus larvatus, have a deeper, 
narrower skull, and a dental formula of ^ f , ci, m ^. The difference 
seen in the teeth of the different specimens of Nythosaurus larvatus is 
due to those in some specimens being of the first set and in others 
the replacing set. 
In Galesaurus planiceps 10 molars occupy 20 mm. ; in Nythosaurus 
larvatus 7 molars occupy 20 mm. 
SCALOPOSAUEUS. 
Among the many forms described by Owen in 1876 few are more 
interesting than the small skull described as Scaloposaurus constrictus. 
No other specimens have ever been discovered of the form, and the 
original type has apparently never been re-examined since Owen's 
time. The skull proves to belong to the Therocephalia, but it differs 
in many ways from any other known Therocephalian. The canines 
are only slightly enlarged, and there appear to be three — two small 
ones followed by the main canine. The jugal arch is very slender, 
and the postorbital arch does not seem to be complete — in this resembling 
the condition in Bauria. Dr. Smith Woodward has kindly had the palate 
partly cleared at my suggestion, and so far as displayed it is typically 
Therocephalian, but there appear to be no teeth on the pterygoids. The 
lower jaw is mainly formed by the dentary, which is remarkable for the 
small development of the coronoid process. The angular and surangular, 
though smaller than usual, are quite Therocephalian in structure. 
Scaloposaurus is particularly interesting in being the smallest known 
Therocephalian. In the small coronoid process and the feebly developed 
canines it approaches Galechirus, but in the imperfect development of the 
postorbital arch it differs from all other known Therapsidans except the 
Cynodont Bauria. The dental formula is probably ^ 6, c 3, m 9. 
GOKGONOPS. 
In 1876 Owen described a very remarkable skull under the name 
Gorgonoj^s torvus. Though somewhat like other Theriodont " skulls 
Owen recognised in it some distinctive characters, and placed it in a 
special group, the Tectinarialia. Lydekker, who regarded the skull as 
completely roofed, believed Gorgonops was somewhat intermediate between 
Pareiasaurus and the " Theriodonts." On re-examining the skull it 
appears that though the parietal region is broad there is a distinct 
temporal fossa, and the condition is very similar to that seen in Titano- 
suchus, which appears to be its nearest ally. 
