112 RECORDS OF THE AUSTRALIAN MUSEUM. 



each is encircled by five bones, namely the maxillary, pi-efrontal, 

 frontal, postfrontal, and jugal. The bony external nostril is very 

 large, wider than deep, and is bounded by the single premaxillary, 

 the maxillaries and prefrontals. The oi'bital margin of the post- 

 frontal is greater than that of the prefrontal, that of the frontal 

 being smallest of the three. The suture between the postfrontal 

 and parietal is shorter than that between the postfrontal and 

 frontal. The parietals, though laterally expanded, do not roof over 

 the temporal regions, the fossae extending forward to the post- 

 fi'ontrals : the latter bones are separated from the squa- 

 mosals by the quadrato-jugal. The maxillary is sutured with 

 the quadrato-jugal below the jugal. The quadrate forms a 

 complete frame to the tympanum, the deep quadrato-jugal and 

 squamosal just failing to meet abo^e. The quadi-ate is not 

 completely closed behind, and the posterior notch, though wdde, is 

 not deeply cleft ; its lower surface bears two articular facets. The 

 supraoccipital process is extensive and its inferior margin is 

 laterally expanded forming a spoon-shaped plate whose width 

 exceeds the greatest depth of the crest. Tlie foramen magnum is 

 an even oval, deeper than broad and is bounded by the supra- 

 occipital and the exoccipitals. The elements are not apparent in 

 the occipital condyle. The vomer is small and if naturally 

 connected with the premaxillary, the slender process has been 

 bioken away. The prefrontals are connected with the vomer and 

 palatines by a broad thin process developed from the prefrontals, 

 the sutures being close to the vomer and not to the roof of the 

 snout : the lateral view through both orbits is thus, not as usual, 

 but mainly through the palato-maxillaiy foramina. The palatines 

 are laige, sepaiated in front by the small V-shaped vomer, but 

 extensively in contact on the mid-line. The basisphenoid is large, 

 widest behind where it is in contact with the basioccipital ; these 

 bones are evenly sutured, the first-named not forming a shelf 

 below the latter. The pterygoids are long and narrow, in contact, 

 in front, with the maxillaries : they are wholly sepaiated by the 

 basisphenoid and are produced backwards to form the outer 

 boundaries of the basioccipitals. At the side of the basisphenoid 

 each pterygoid develops a lateral process which is separated from 

 the quadrate by a deep groove. The connection between the 

 parietals and pterygoids is carried forward, below to the palatines, 

 and above, to the suture between tlie prefrontals and frontals. 

 The lamella? thus formed broaden laterally in front and meet on 

 the mid-line, and they run so close to the prefronto-palatine 

 connection, before described, that it is not possible to pass an 

 object as thin as a penknife blade, through the orbits, between 

 them. 



