380 Mr. C. W. Andrews on the Skull, 



this and the side of the basi-teraporal platform there is a 

 funnel-shaped depression, at the bottom of which a foramen, 

 probably that transmitting the internal carotid {car.for.), 

 opens. Immediately above, and somewhat to the inner 

 side, of this is the vagus foramen (x,). In the middle line, 

 between the bases of the basi-pterygoid processes, there is a 

 circular foramen, which seems to penetrate into the brain- 

 case ; this opening is the anterior basi-cranial fontanelle, 

 occasionally present in Dinornis. 



In both specimens the rostrum and the cuds of the basi- 

 pterygoid processes are broken away. 



The tympanic cavity is shallower than in the Dinornitliidse, 

 owing mainly to the fact that the inner angle of the par- 

 occipital process is less prominent ; on the other hand, the 

 greater width of this process makes the cavity wider than in 

 the New Zealand bird. The margin forms an even curve, 

 much as in Dinoj'nis. On the roof of the tympanic cavity, 

 immediately internal to the zygomatic process, is the articular 

 facet for the quadrate ; the form of this articulation, and the 

 share in its composition taken by the various bones, are shown 

 in fig. 7 of Plate VIII. It is more circular in outline than in 

 tlie other Struthious birds, and is very deeply concave. The 

 various foramina opening into the tympanic cavity are 

 arranged almost exactly as in the Dinornithidae, The an- 

 terior tympanic recess and the pretemporal wings are very 

 large. On the left side in the specimen figured the columella 

 auris is still in place. 



The temporal fossa {t.f., fig. 3) is very deep and narrow, 

 and its anterior and posterior borders are nearly parallel. 

 On the upper surface of the skull the fossee are widely sepa- 

 rated one from another, the interval between them being about 

 equal to the width of the interorbital region of the frontals. 

 There is a large, nearly flat, posterior temporal fossa {post. t.f.), 

 bounded internally by the inferior tympanic ridge, which is 

 not produced into a pre-tynipanic process, and externally by 

 the post-temporal ridge, which forms the antero-external 

 margin of the zygomatic process. The squamosal does not 

 form a prominence as in the Dinornithidae, but has a nearly 



