PHYLOGENT OF THE PAL^EOGNATH^E AND NEOGNATtLE. 187 



The quadrato-jugal fossa extends forwards to within a short distance of the anterior 

 border of the posterior nares. 



In Crypturi the maxilla resembles that of Rhea, but its maxillo-palatine process is 

 much narrower and is unfenestrated. There is no antrum. The lachrymo-nasal fossa 

 is bounded anteriorly by a descending process of the nasal and not by a spur from the 

 maxillo-palatine as in Rhea. 



In Apteryx the maxilla is of great size, its maxillo-palatine processes, seen ventrally, 

 extending forwards to the middle of the elongated beak, and backwards along the outer 

 border of the palatine to within a short distance of the level of the free end of the 

 orbital process of the quadrate. They are separated one from another in the middle line, 

 forwards, only by the narrow vomer. Posteriorly there is an external lateral spur for 

 articulation with the quadrato-jugal bar. The proximal mesial border is closely fused 

 with the external border of the short palatine. There is no antrum. Immediately in 

 front of the distal end of the palatine the maxillo-palatine process occasionally sends 

 inwards a very short process to articulate with the vomer, which apparently 

 corresponds with the much larger vomerine process found in Struthio. 



The quadrato-jugal is so reduced in size in Casuarius as to be represented by little 

 more than a nodule of bone, scarcely projecting beyond the limits of the glenoid cup 

 of the quadrate. 



The jugal in Casuarius is connected by a close vertical suture with the quadrate 

 portion, and projects above it at this part in the form of a more or less prominent 

 spine. It extends forwards as far as the middle of the lachrymo-nasal fossa. 



In Dromceus, seen from the outside, the quadrato-jugal scarcely exceeds that of 

 Casuarius (PI. XLIII. fig. 4«). On the inner side, however, it extends forwards along 

 the jugal for about one-third of its length. In Casuarius it does not extend beyond 

 the rim of the quadrate cup on the inside. The forward extent of jugal is about the 

 same as in Casuarius. 



Rhea and Struthio resemble Dromceus in the size and relations of these two bones. 



In Apteryx the quadrato-jugal is a long slender style, reaching as far forwards as the 

 middle of the zygomatic arch. The jugal is long and slender, extending forwards 

 along the dorsal aspect of the quadrato-jugal as far as the level of the anterior 

 extremity of the palatine, which corresponds with a line drawn transversely across the 

 vomer about its middle. 



In Crypturi the quadrato-jugal is as much reduced as in Casuarius. The mesial 

 border of the proximal end of the jugal articulates, as in this form, with the quadrate. 



The Vomer, Pterygoid, and Palatine (see also p. 206). (PI. XLII. figs. 5-8.) 



In Casuarius the vomer is of great length and slenderness. In C. c. salvadorii, 

 C. c. sclateri, and C. c. beccarii it is cleft from behind forwards for more than half its 



