370 H. L. KESTEYEN. 



(processus praefrontalis)[2\ and palatine process (processus 

 palatums) [3], The alveolar plate, flattened from side to 

 side, is of quadrilateral outline, its anterior margin (margo 

 pruemaxillaris) [4] articulates with the premaxilla. The 

 posterior margin is bevelled at the expense of the outer 

 table to form a squamous-suture surface for the jugal (fades 

 jugalis) [5]. Superiorly this plate is flush with the outer 

 surface of the prefrontal process in front, but further back 

 its upper margin forms the lateral boundary of the floor of 

 the orbit (margo orbitalis) [6]. The medial surface is 

 covered by the palatine process above, and below this is 

 sculptured by wide perpendicular grooves and intervening 

 narrow ridges. The prefrontal process anteriorly forms 

 the lateral boundary of the anterior narial aperture (margo 

 nasalis) [7], behind it forms the lower half of the anterior 

 boundary of the orbit (margo orbitalis) \8]. The medial 

 surface supplies the lower half of the lateral wall of the 

 nasal chamber (fades nasalis) [9], above this nasal surface 

 is an area for articulation with the prefrontal (fades 

 prae frontalis) [10]. The palatine process bears on its oral 

 surface (fades palatums) [11] a row of tooth-like conical 

 tubercles on the crest of a longitudinal ridge (agger mas- 

 ticatorius) [12]. Above, the palatine process enters into 

 the formation of the floor of the orbit {fades orbitalis) [13 ] 

 in its posterior portion and the floor of the nasal chamber 

 further forward (fades nasalis) [14]. The nasal and orbital 

 surfaces are separated by a backward and medially pro- 

 jecting buttress of the prefrontal process, which for the 

 greater part articulates with the nasal plate of the pre- 

 frontal, but in its lower portion presents a free prominent 

 ridge, (margo lacrymalis) [15]. The medial edge of the 

 palatine process articulates from before backwards with 

 premaxilla [10], vomer [ 17] and palatine [18]. 



The Palatine (Ob palatinum) [Figs. 6, 7, and 8] consists 

 of an irregularly rhomboidal, flat, stout plate of bone [1], 



