A NEW FOSSJL RUMINANT GENUS. 7 



the fossil. They start so erect from the brow that their axis is perpen- 

 dicular to their basement : and they diverge at a considerable angle. From 

 their base upwards they are free from any rugosities, their surface being 

 smooth and even. They are evidently the osseous cores of two intra- 

 orbital horns. From their position and size they form one of the most 

 remarkable features in the head. The connections of the frontal are no- 

 where distinguishable, no mark of a suture remaining. At the upper end 

 of the bone the skull is fractured and the structure of the bone is exposed. 

 The internal and outer plates are seen to be widely separated, and the 

 interval to be occupied by large cells, formed by an expansion of the diploe 

 into plates as in the Elephant. The interval exceeds 2^ inches in the 

 occipital. On the left side of the frontal, the swelling at the vertex, has its 

 upper lamina of bone removed, and the cast of the cells exhibits a surface 

 of almond-shaped or oblong eminences with smooth hollows between. 



The temporal is greatly concealed by a quantity of the stony matrix, 

 which has not been removed from the temporal fossa. No trace of the 

 squamous suture remains to mark its limits and connection with the fron- 

 tal. The inferior processes of the bone about the auditory foramen have 

 been destroyed or are concealed by stone. The zygomatic process is long 

 and runs forward to join the corresponding apophysis of the jugal bone, 

 with little prominence or convexity. A line produced along it would pass 

 in front, through the tuberosities of the maxillaries, and to the rear along 

 the upper margin of the occipital condyles. The process is stout and 

 thick. The temporal fossa is very long and rather shallow. It does not 

 rise up high on the side of the cranium ; it is overarched by the cylinder- 

 like sides of the frontal bone. The position and form of the articulating 

 surface with the lower jaw are concealed by stone which has not been 

 removed. 



There is nothing in the fossil to enable us to determine the form 

 and limits of the parietal bones : the cranium being chiefly mutilated 

 in the region which they occupy. But they appear to have had the 



V 



