aoe ROY L. MOODIE 
The brain cast of a related and contemporary form Hoplo- 
phoneus, a large, heavier-limbed cat, has been briefly and 
inadequately described and figured by Bruce (’83). The dis- 
cussion of an endocranial cast which may represent Hoplophoneus 
is given below. 
The cerebrum, almost all neopallial in nature, of this primitive 
cat, Dinictis, is quite short and thick (fig. 4), and the simple 
cerebral pattern is evident and clearly impressed on the indurated 
material preserved. The lateral sulcus (S.lat.) runs almost 
parallel to the sinus sagittalis, ending gradually and without 
complexity. At its anterior end this sulcus appears to converge 
with a slight depression which may represent the coronal suleus 
and with the termination of the suprasylvian sulcus (S.ss.).. The 
prominence of the endocranial venous sinuses may be correlated 
with the well-developed sagittal crest which the skull exhibits. 
The crest is, however, slight compared to its development in 
Hoplophoneus. The suprasylvian sulcus (S.ss.) runs approxi- 
mately parallel to the lateral sulcus, these two being the only 
clearly marked evidences of cerebral complexity seen on the 
dorsum of the cerebrum. ‘This gives the cerebrum a remarkably 
simple aspect, as would be expected from the primitive organi- 
zation evidenced by the skeleton. Meningeal vessels are not 
evident and the rhinal fissure is not preserved. 
The olfactory region was lost as shown in figure 4, X. The 
broad broken surface of the olfactory bulb, however, indicates a 
highly developed sense of smell, for the cats have apparently 
always been predatory. A comparison of the cerebral features 
of this cat (fig. 4) with the Pleistocene cat (fig. 16) reveals in a 
striking manner its evolution. 
The form of the cerebellum, as seen from above, is only indi- 
cated by the material preserved, since the cast had been badly 
broken in this place before coming into my hands. ‘The relative 
size of the cerebellum to the cerebrum and its relation to the 
broad medulla are worthy of note. There is no indication from 
the specimen of the cerebrum’s bulging over the cerebellum 
such as is commonly seen in modern carnivores. 
