THE SKELETON OF THE DOG. THE SKULL. 397 



17. maxilla (palatal portion). V 2 . foramen rotundum. 



18. posterior palatine foramina. V 3 . foramen ovale. 



19. anterior palatine foramen. VII. stylomastoid foramen. 



20. premaxilla. IX, X, XI. foramen lacerum pos- 



21. alisphenoid canal. terius. 



22. Eustachian foramen. XII. condylar foramen. 



23. postglenoid process of squa- i 2. second incisor. 



mosal. c. canine. 



II. optic foramen. pml, pm4. first and fourth pre- 



III, IV, Vj, VI. foramen lacerum molars. 



an terius. in 1. first molar. 



posterior of them is the pterygoid (fig. 75, 15), a thin verti- 

 cally placed plate of bone, which articulates above with the 

 basisphenoid, the presphenoid, and the strong pterygoid pro- 

 cess of the alisphenoid. The ventral end of the pterygoid 

 is drawn out into a small backwardly-p rejecting hamular 

 process. In front the pterygoid articulates with the palatine, 

 a much larger bone, consisting of (1) a vertical portion, which 

 passes up to meet the orbitosphenoid and frontal, and sends 

 inwards a plate which meets the presphenoid and vomer, form- 

 ing much of the roof of the posterior part of the narial passage; 

 and (2) a strong horizontal portion, the palatal process (fig. 

 75, 16), which passes inwards and meets its fellow in the 

 middle line, forming the posterior part of the bridge of bone 

 supporting the hard palate. The palatal process is continuous 

 in front, with a large bone, the maxilla, which, like the pala- 

 tine, consists of vertical and horizontal portions. The vertical, 

 or facial portion (fig. 73, 5), i& the largest, and constitutes 

 the main part of the side of the face in front of the orbit, form- 

 ing also the chief part of the outer wall of the nasal cavity. 

 It is continuous in front with the premaxilla, above with the 

 nasal and frontal, and behind with the lachrymal, jugal, and 

 palatine. The horizontal, or palatal portion (fig. 75, 17), 

 forms the anterior part of the bony plate supporting the hard 

 palate, and meets its fellow in a long straight symphysis. The 

 junction line between the palatal and facial portions is called 



