32 



THE BONES AND JOINTS. 



Fkr. 1 8. 



Origin of the suspensory 



by a movable joint. Externally the 

 articular head curves somewhat abruptly 

 into the bony substance (Fig. 18 pt) 

 of the pterygoid bone. 



10. The maxillary bones, ossa 

 cartilage maxillaria superiora, (^uvier (Figs. 10, 



(«p) from the skull, with attachment -, j ., ^ \ c\ m\ 

 of the pterygoid ; front view. Ciir- ' • ^ -^ ■' * 



tilage shown by stippling. , „ -r,, -.^,,-ttt -r^. . . 



* ^ ° Cuvier, /. c, p. 3S9, PI. XXIV, Figs, i, 2 k k. 



— Dugès, n. 4, maxiUo-jiigal. — Parker 



and Bettany, J. c, maxillary bones. 



These are elongated, curved bones, 

 narrower behind, broader in front, and 

 forming with the quadrato-jugals the 

 bony support of the 

 face. The suj)erior 

 surface is convex and 

 directed outwards, the 

 inferior surface is 

 grooved and bears 

 teeth along the outer 

 edge of this groove. 

 From the upper and 

 inner border of the 

 anterior half of this 

 bone a process {pro- 

 cessus frontalis) passes 

 upwards, which articu- 

 lates with the nasal 

 bone. The anterior ex- 

 tremity of the bone 

 articulates with the 

 premaxillary bone, the 

 posterior with the quad- 

 rato-jugal. 



The maxillary bone 

 articulates at its an- 

 terior end (Fig. 19 n') 

 with a process of the 

 cartilaginous capsule 

 of the nose. The broad plate of cartilage (Fig. 19 v), under 



Cartilaginous skull of Rana csculenta, from below, twice 

 natural size. Cartilage shown by stippling. 



for 



c Cartilage of pi'ootic. 

 e Sphenethmoid. 

 fp Fronto-parietal. 

 « Premaxillary. 



Quadrato-jugal. 

 m Maxillary. 

 n,sn Cartilaginous nasal skele 



ton. 

 «', n", n'", n"" Processes of $p' Cartilage 



nai;al cartilage. mosal. 



o Exoccipital. sp" Cartilage under ptery 



p Prootic. gold. 



pi Palatine. v Vomer. 



r>t Pterygoid. 



pt' Articular surface 



pterygoid. 

 r Optic foramen. 

 r' Foramen for N. abducens. 

 s Parasphenoid. 

 s' Cartilaginous cranium. 

 sp Cartilage of susjiensorium 

 under squa 



