( 190) 



is small : in A nomalopteryx parva, on the other hand, it is as large as in the 

 present specimen, and the temporal and lambdoidal ridges meet ; there are, however, 

 many differences in the arrangement of the inferior and posterior temporal ridges. 



Tlie outline of the orbit is evenly curved or very slightly sinuous, and, owing to 

 the backward direction of the postorbital process, it seems to be larger than in the 

 other genera, in which also the preorbital process is much smaller. The optic 

 foramen is circular in outline, and it is situated as in Meimiornis. There is a large 

 and deep presphenoid fossa. 



The mesethmoid is not perforated posteriorly by a fenestra, so that the olfaitorv 

 chambers are completely separated by bone. The outer border of the antorbital 

 plate, which is of very small vertical extent, is not fused with the lachrymal, the 

 lower end of wliioh is ])erforated by the lachrymal foramen as in Anoinalopteryx 

 didifcn'mis. The alinasal appears on the surface of the skull, filling the angle 

 between the nasal and lachrymal. 



The beak is pointed as in Meimiornis. The anterior i)ortion of the nasal 

 process of the jjremaxillae, where it joins the body of the bone, is thin, thus 

 differing widely from the same region in Mesapteryx, Anomaloptei-yx, and, es-pecia.\\y, 

 Emeus. 



Seen from above the roof of the skull presents a nearly evenly arched surface. 

 The most notable characteristic is its great breadth between the orbits, much greater 

 than in Meioruyrnis and Anomalopleryx. 



The only peculiarity noticeable ou the ventral aspect is the length of tlie 

 pedunculate basi-pterygoid processes. 



The mandible is more slender than that of any other of the ;\Ioas, the depth .at 

 the level of the slightly indicated corouoid process being only 13 mm. The symphysial 

 region is short and pointed. The articular surface for the quiuhate is broad ; the 

 posterior angular process is smaller than in Anovialopteryx and Mesopten-yx, but on 

 the other hand the internal angular process is much larger. 



The general characters of the skull may be summarised as follows : — 



Width of cranium at paroccipital processes less than half length of basis cranii. 



Distance between optic foramina a little more than one-third length of basis 

 cranii. 



Orbit evenly curved. 



Length of premaxilla less than two .and a half times that of basis cranii. 



Body of premaxilla pointed and slightly decurved ; its length and breadth less 

 than b.asis cranii. 



The occipital plane slightly inclined backwards. 



The occipit.al condyle pi-ojfc(ing slightly beyond the paroccipital processes. 



Anterior and posterior lambdoidal ridges sejiarated by a very narrow interval in 

 their middle region only. 



Width at .squamosals slightly more than double length of basis cranii. 



jNIammillary tuberosities not very prominent. 



iMargin of tj'mpanic cavity evenly curved. 



Temporal fossae very large; distance between tem[ioral ridges aboutr four-fifths 

 width of cranium at fossae. 



The posterior temporal ridge confluent with lambdoidal ridge ; posttemporal 

 fos.sae very large. 



The inferior temporal ridge is strongly marked and there is a pretympanic 

 process. 



