206 ME. W. P. PYCKAFT ON THE MOKPHOLOGY AND 



The sujn-a-angular, iu all, articulates proximally with the articular. Its dorsal 

 border is received between the right and left moieties of the superior limb of the 

 dentary. Its ventral border descends caudad to the level of the inferior border 

 of the angular; distad it rises gradually so as eventually to cross the dorsal border of 

 the same. 



The coronary is in all a short, slender, and rod-like bone. In many Neogiiatli(e it 

 is often of considerable size and laterally compressed. 



In all the Palceognatlm it appears to extend backwards so as to embrace the 

 inner border of the articular and to form the internal boundary of the articular surface 

 for the quadrate. In Ehea and Apteryx it is very feebly developed distad, and may be 

 described as vestigial. In Casuarius and Uromceus it is much larger. Struthw is 

 intermediate. In no case does it extend forwards beyond the posterior third of the 

 ramus. 



Such characters of the skull as are of use ibr systematic purposes will be found iu 

 the " Keys " at the end of this paper. 



More material is needed before these can be made complete, since a " Key " to the 

 species has not been possible in the case of Casuarius. Whether the characters 

 considered to be specific in the case of the other genera will stand the test of time 

 remains to be seen. In several instances I have been obliged to rely upon the characters 

 of a single skull, as in the cases of the skulls of Ehea macrorhyncha, for instance. 



I feel justified in reviving Dr. Sclater's Struthio meridionaUs [90] on account of the 

 many marked peculiarities which the skull and the trunk of this skeleton presents. 



The work of distinguishing the skulls of the four species of Apteryx has been a very 

 difficult one. Indeed, as Mr. Beddard has already remarketl [8], " the very slightest 

 differences, apart from those of size, distinguish the Apteryges." 



Some Poikts of SIGNIF1CA^•CE ix the Struthious Palate. 



The following points appear to be worthy of special consideration and may fitly be 

 discussed here. 



In comparison with the palatines of the NeognathoB, it will be remarked that in 

 Rhea, as iu the other Paloeognathce, the palatines are widely separated one from 

 another by the laterally expanded feet of the vomer. In the Neognathoe the palatines 

 meet iu tlie middle line, thrusting the vomer forwards, so that it now appears to 

 articulate not with the pterygoid but with the palatines. In Rhea and Crypturi we 

 have probably a clue to the way in which this has come about. Turning once agaiu 

 to the skull of Uromceus, we notice that the palatines are only loosely attached to the 

 outer border of the vomerine feet, whilst in Rhea (PI. XLII. fig. 5) the palatines have 

 moved inwards so as to overlap these feet and approach one another mesially. Their 



