138 SKELETON OF THE OX 
rates the two palatine sinuses. The alveoli for the cheek teeth increase in size 
from before backward. The maxillary sinus proper is small and is undivided. 
The maxillary foramen is a narrow fissure, deeply placed at the medial side of the 
lacrimal bulla. The maxilla takes no part in the formation of the palatine canal. 
Sutural (or Wormian) bones are often present at its Junction with the lacrimal and 
malar bones. 
The body of the premaxilla is thin and flattened, and has no alveoli, since 
the canine and upper incisor teeth are absent. A deep notch takes the place of 
the foramen incisivum. The nasal process is short, convex laterally, and does not 
reach to the nasal bone; the space between the two processes is greater than in the 
horse. The palatine process is narrow and is grooved on its nasal surface for the 
septal cartilage and the vomer. The palatine fissure is very wide. 
The palatine bone is very extensive. The horizontal part forms one-fourth or 
Frontal 
eminence 
Frontal bone 
Nasal bone 
en 
Fie. 135.—Sacrrran Section oF SKULL or Ox, witHouT MANDIBLE. 
A, A’, Squamous and basilar parts of occipital bone; B, B’, postsphenoid, presphenoid; C, lateral mass of ethmoid 
bone; D, internal plate of frontal bone; #, parietal bone; F', petrous temporal bone; G, pterygoid bone; H, perpendicu- 
lar part of palatine bone; J, outline of vomer (dotted line); J, palatine process of maxilla; K, nasal process of premaxilla; 
L, dorsal turbinate bone; M, ventral turbinate bone; N, middle turbinate bone (great ethmo-turbinate); 1, occipital 
condyle; 2, paramastoid process; 3, bulla ossea; 4, basilar tubercle; 5, muscular process; 6, hypoglossal foramen; 7, 
openings of condyloid canal; 8, direction of condyloid canal (dotted line); 9, internal opening of temporal canal; 10, 
meatus acusticus internus; 11, foramen lacerum; 12, sella turcica; 13, optic foramen; 14, sphenoidal sinus; 15, orbital 
wing of sphenoid bone; 16, frontal sinus; 16’, anterior limit of frontal sinus (dotted line); 17, dorsal nasal meatus; 18, 
middle nasal meatus; 18’, dorsal branch of middle meatus; 19, ethmoidal meatuses; 20, maxilla; 21, sphenopalatine 
foramen; 22, opening into maxillary sinus; 23, opening into palatine sinus, and arrow indicating communication of 
latter with maxillary sinus; 24, palatine sinus; 25, cross indicates anterior end of palatine sinus; 26, palatine fissure. 
more of the hard palate. The anterior palatine foramen opens near the junction 
with the maxilla, about half an inch from the median palatine suture and crest. 
Accessory palatine foramina (Foramina palatina accessoria) are also present. The 
palatine groove is usually not very distinct. The palatine canal is formed entirely 
in this part, and there is no articulation with the vomer. A rounded ridge occurs 
on the nasal side of the median suture. The interior is hollow, forming part of the 
palatine sinus. The perpendicular part is an extensive, quadrilateral, thin plate, 
which forms the posterior part of the lateral wall of the nasal cavity and in part 
bounds the choane or posterior nares. Its nasal surface is nearly flat, and is smooth 
and free, except behind, where it is overlapped by the pterygoid bone. The lateral 
surface is attached to a small extent to the pterygoid process behind, and is free else- 
where. The sphenopalatine foramen is a long, elliptical opening, formed by a deep 
notch in the upper edge of the palate bone and completed by the ethmoid and sphe- 
