192 ME. W. P. PYCKAPT ON THE MOBPHOLOGY AND 



in form, with the external border produced backward into a pointed spur which runs 

 along the pterygoid, and forwards for a considerable distance along the maxilla. Its 

 mesial border is cut away anteriorly so as to embrace the external border of the vomer 

 instead of underlying it, as is done by the remaining posterior portion. Its form is 

 seen best from the ventral aspect of the skull. 



In the Dinornithicfce, e. g. Emeus, the form of the palatine resembles that of Rhea, 

 but by a little tension the body of the bone has come to be vertical instead of hori- 

 zontal in position, thus giving a rod-shaped superficial appearance. 



In the Crypturi the main body of the palatine is, as in Bhea, horizontal, but the 

 anteriorly produced external lateral border is of much greater length, and takes the 

 form of an elongated and slender rod suturating anteriorly with the maxilla. 



In Struthio the palatine (PL XLII. fig. 8) resembles that of many Carinatce in that 

 the main body of the bone is twisted into the form of an almost vertical scroll. It is 

 peculiar, however, in that it is fused at its base with the overlapping pterygoid. The 

 external lateral border is produced forwards, as in Tinamous, into an elongated slender 

 rod, but which fuses anteriorly with the base of the hastate maxillo-palatine process. 



In Apteryx the palatine (PL XLII. fig. 5) takes the form of a more or less flattened 

 rod, differing in its relations from all the other associated forms. Anteriorly, it 

 is fused with the maxillo-palatine process. The greater part of its external border is 

 anchylosed with the maxilla. 



The remaining posterior end of this bone anchyloses with the external border of 

 the pterygoid. What corresponds with the posterior region of the mesial border in 

 Dromceus is here free, and runs in a backwardly transversely oblique direction across 

 the skull. For the precise relations of the bone however, see p. 204. 



The Quadrate. (PL XLIII. figs. 10-12.) 



The quadrate in Casuarius has its various processes very sharply defined. 



The otic process is very slender, tapering gradually downwards into the body of the 

 bone. At its base, where it merges into the main body, is a large pneumatic foramen, 

 it opens on the posterior surface. The head for articulation with the pro-otic and 

 squamosal is single, oblong in form, with its long axis directed backwards and inwards. 



The inner and outer mandibular condyles join mesially, the two projecting backwards 

 to form a conspicuous spur. The difference in the level of the two condyles is but 

 slight. 



The orbital process is well defined, moderately large and free, with a sinuous 

 superior border. At its extreme base, and on its inner side, is a small demi-facet for 

 the pterygoid. 



The outer surface of the quadrate is very closely applied to the long stout zygomatic 

 process of the squamosal, which terminates only a short distance above the level of the 

 cup-shaped quadrato-jugal fossa. 



