180 Transactions of the South African Philosophical Society. 
the anterior fifth they are either absent or lost. Probably there have 
been some small incisors and a small canine such as is seen in the 
long slender jaw of Perameles nasuta, but no distinct indications of 
them remain. .The jaw has been loosely articulated with its neigh- 
bour by a rather long symphysis somewhat similar to that seen in 
many Marsupials. The coronoid process is remarkably well 
developed, and is not only of great length, but is unusually thick. 
It forms an angle with the axis of the ramus of about 120°. The 
splenial appears to be only a feeble splint closely applied to the 
dentary. The articular is lost. The anterior of the teeth of the 
lower jaw are simple sharp conical teeth, very similar to those of the 
upper jaw, and, like them, ridged. The posterior four teeth are also 
very simple in structure, but have more rounded apices and are more 
feebly ridged. 
In only a few of the many described Theriodont genera is the 
skull at all satisfactorily known; and in those the skull differs 
‘very considerably from that found in Ictidosuchus. In some of 
the higher Theriodonts, e.g., Gomphognathus, the frontal bones 
are excluded from the orbits by the meeting of the prefrontais and 
postirontals. In Ictidosuchus, as in Dicynodon and most Anomo- 
donts, the frontals form a part of the supraorbital ridge. In the 
higher Theriodonts the parietal foramen is absent or rudimentary, 
though in Galesaurus, and probably the majority of lower Theriodonts, 
there is, as in Ictidosuchus, a well-developed parietal foramen. In 
the structure of the squamosal the affinities of Ictidosuchus are 
apparently more with the Anomodonts than with the majority of the 
Theriodonts. As regards the structure of the postorbital and 
temporal arches the condition in Ictidosuchus differs considerably 
from that in Cynognathus and is essentially similar to that in most 
Anomodonts. It is probable, however, that in most of the lower 
Theriodonts the structure of the arches is very similar to that in the 
Anomodonts. The lower jaw, so far as known, is thoroughly 
Theriodont in structure. 
SHOULDER GIRDLE. 
Of the shoulder girdle, the scapula, the coracoid,.and the precora- 
coid of the left side are well preserved, and they present one or two 
characters in which they differ from those bones in the previously 
known South African forms. The scapula, though very broad at its 
base, is for the most part a long slender bone, with its axis so much 
curved that a tangent to the upper end of the bone would make 
with a tangent to the lower end an angle of about 100°. In the 
middle region the scapula is narrow and flattened, with a rounded 
