bearing a more expansive but lighter orbital plate [2] 

 dorsally. The ventral surface [3] flush with the rest of 

 the palate bones is like them deeply pitted. The antero- 

 medial margin [I | articulates with the vomer, the antero- 

 lateral [5] with the maxilla, the postero-lateral |G] with 

 the pterygoid process of the jugal, whilst the postero- 

 medial margin [7] forms the greater part of the arcuate 

 margin of the palate bounding the naso-palatine fossa [68, 

 fig. 47]. The dorsal surface is divided by the attachment 

 of the orbital plate into an anterior and medial nasal sur- 

 face [8] and a posterior orbital surface [9]. The orbital 

 plate extends upward and medially to articulate with the 

 vomer and its fellow of the other side (margo sagittalis) 1 10] 

 roofing the posterior nasal passage and forming portion of 

 the floor of the orbit, there is thus formed between the two 

 plates a deep nasal sulcus [11]. The posterior margin 

 articulates with the pterygoid [12], the anterior margin is 

 free and forms the posterior margin of the lachrymal fora- 

 men [13]. 



The Vomi:k | Pigs. i), 10, 11, and 12| consists of a ver- 

 tically placed body [1] bearing palatine [2], prefrontal |3] 

 and pterygoid [4| processes. The body is interposed 

 between the two posterior narial passages, stouter in front 

 than behind, it bears above the prefrontal processes, and 

 between these is deeply grooved (sulcus ethmoidalis) [5]- 

 Behind the ethmoidal sulcus the upper surface of the body 

 forms a median strip of the floor of the orbits {fades 

 orbitalis) [6]. The palatine process is a horizontally 

 expanded plate of bone, about twice as long as broad, its 

 palatine surface is strongly concave in both directions [13]. 

 It forms a broad central area of the palate, articulates in 

 front with the premaxillae |7], and laterally with maxillae 

 [8 1 and palatines 1 14], and forms the median segment of the 

 arcuate margin of the palate [9 J. The conical pr.'ir.mial 



