Loxomma Alhnauni in the NorthuinherJand Coal-field. 375 



great lateral expansions which form the sides, of the occipital 

 region. In front it is a little expanded laterally, and mea- 

 sures two and a quarter inches across ; thence backwards for 

 two and thi'ee-quarter inches the sides arch gently inwards, 

 forming the inner anterior boundaries of what may be termed 

 the anterior division of the orbits ; and then for an inch 

 and three-quarters further back the sides are more strongly 

 arched in the same direction, forming the inner posterior 

 boundaries of the posterior division of the orbits, there 

 being at the junction of the two divisions of the inner orbital 

 boundary a strong angular projection, emphatically marking 

 off the two parts. At this point the interorbital bone is two 

 inches wide. A little further back, at the narrowest part, it is 

 only an inch and three-eighths wide. The inner boundaries 

 of the orbits appear to be formed by the pre- and post- 

 frontals. 



The posterior portion of this central strip reaches from the 

 hinder margin of the orbits to the occiput, the sides being very 

 slightly arched outwards, and continuous with the lateral ex- 

 pansions. This portion of the cranium is two inches and six- 

 eighths wide, and two inches and three-eighths long, measur- 

 ing from the posterior boundary of the orbit to the point of 

 the epiotic bone, and, rising a little above the general surface, 

 is strongly defined. The occipital margin is slightly arched 

 inwards, and at either side is produced backwards into short 

 horns — the posterior points of the epiotic bones. This division 

 of the central strip of bone is composed of the occipitals, the 

 parietals, a portion of the postfrontals, and the epiotics, though 

 here, as in the anterior division, the boundaries cannot be 

 determined with precision. No parietal foramen can be ob- 

 served. 



The lateral expansions are each three inches wide, and, ac- 

 cording to Prof. Huxley, they are composed of the postorbitals, 

 the malars or jugals, the squamosals, and the quadrates. 

 They project backwards quite an inch and a half beyond tlie 

 central portion of the skull. The hinder margin of each at 

 first bends outwards and backwards from the side of the epiotic 

 bone for about two-thirds of its extent ; it then suddenly turns 

 a little forwards and terminates in a short point at the lateral 

 or external angle. From the base of this point the outer or 

 lateral margin advances forwards and outAvards, being at first, 

 for about an inch, a little concave ; it then bends a little in- 

 wards, and runs forwards in a straight line an inch and five- 

 eighths further to the posterior extremity of the maxilla. 

 From this point, which is only slightly indicated, the lateral 

 walls of the skull are continued in a uniformly inclined line to 



26* 



