376 Messrs. Hancock & Atthej on the Occurrence of 



the anterior extremity. The inner part of the posterior mar- 

 gin is formed by a ridge whicli thickens and enlarges at the 

 point where it turns suddenly forvvards, and this thickened 

 part is turned upwards and overlaps a little the upper surface 

 of the skull ; thence to the external point or horn the surface 

 is smooth, and has the appearance of being that of a joint. 

 This is apparently the tympanic bone. 



The surface-sculpture, however, does not extend so far back 

 as this ; it terminates abruptly in a sigmoidal line that reaches 

 from the outer margin of the epiotic bone about midway be- 

 tween its posterior horn and the hinder boundary of the orbit 

 to the base of the outer cornu. At first this line (th-at is, its 

 inner extremity) arches gracefully forwards, and then sweeps 

 backwards and outwards to its outer termination, as already 

 indicated. Behind this line the bone is depressed and smooth ; 

 the space next the epiotic bone is of considerable extent, and 

 has all the appearance of being for muscular attachment : 

 probably the temporal muscles may originate here ; for mus- 

 cles so placed would be conveniently situated to act upon the 

 articular extremity of the mandible. 



The posterior outer boundary of the orbit is formed by the 

 postorbital, the limits of which can be partially traced ; it is 

 narrow, and extends from the postfrontal to the inner pos- 

 terior border of the malar ; its orbital margin is concave, and 

 is inclined outwards and forwards. The limits of the malar 

 are also pretty well defined ; it is wide behind, before quite 

 narrow, not being more than seven-eighths of an inch wide, 

 including the thickness of the posterior extremity of the 

 maxilla, which forms as it were a narrow border to its straight 

 margin. When perfect, this narrow portion of the malar 

 could not be less than two and a half inches long ; more than 

 two inches of it still remains, the anterior extremity having 

 been broken away. The orbital boundary of this part is only 

 very slightly concave ; it then rather suddenly bends inwards 

 and backwards as it approaches its junction with that of the 

 postorbital, where there is a slight bulging inwards. From 

 this point the posterior margin of the malar is bounded by the 

 postorbital, the squamosal, and th^ quadrate. At first this 

 boundary passes inwards and backwards, then outwards and 

 backwards, and finally forwards and outwards, reaching the 

 straight external margin of the malar at the posterior point of 

 the maxilla. This enlarged posterior portion is upwards of an 

 inch and a half wide. 



The orbits are both imperfect in front, the anterior boun- 

 daries having been broken away ; but the form, notwithstand- 

 ing, is determinable throughout. They are very large, mea- 



