380 he. b. w. rooLi:r on the [June 1913, 



The Jugal. 



The jugal (PL XXXVII, figs. 2 & 0, J.) is a rod-like hollow bone, 

 except at its lower end, where the inner and outer lateral surfaces 

 are flat. It rises obliquely, yet feebly arched, to the lachrymal. 

 Here it is bifurcated into short branches, the outer being club-shaped 

 and passing backwards and downwards, forming a moiety of the 

 anterior margin of the orbit. The inner is rod- like, and connects 

 with the interior border of the lachrymal. The distal termination 

 is V-shaped, one branch joining a raised portion of the inner border 

 of the maxilla and the other being fused with the interior surface 

 of the quadratojugal at its dorsal edge. Its total connexion with 

 tbe maxilla and the quadratojugal is only 5 mm. long. 



The Temporal Arcades. 



The jugal, quadratojugal, and quadrate all rise obliquely from 

 the maxilla at nearly the same angle and free one from the other. 

 The jugal takes no share whatever in the upper temporal arcade : 

 this is formed by the quadratojugal and the squamosal bar. The 

 squamosal bar overhangs externally the hinder end of both the 

 quadratojugal and the quadrate. The lower temporal arcade is 

 made entirely by the quadrate. 



The Palate. 



I have not thought it advisable, owing to its hardness, to 

 clear away the matrix which lies in the angle made by the 

 convergence of the mandibles, for fear of fracturing this end of 

 the beak. On the area of the palate exposed, there is no trace of 

 the internal nasal openings, and it is too near the anterior margin 

 of the external nares for them to be situated in front. 



The Mandible. 



The mandible (PL XXXVII, figs. 1, 2, 4, & 5, win.) is long, and 

 the symphysis short. The alveolar tracts terminate close behind 

 the symphysis. The rami of the mandibles gradually decrease in 

 depth backwards : but their strength is maintained by a correspond- 

 ing increase of the width, and at the articulations the} 7 are bulbous. 

 Near the symphysis they are convex ventrally ; posteriorly they 

 lose this, and become for some distance flat, with a convex upper 

 and lower border. Behind the premaxillse, they lie exterior to the 

 upper jaw. On their inner dorsal margin there is a depressed 

 ledge, on which the maxillae rest, when the jaws are shut. Beneath 

 this shelf, the bone is concave. They terminate far in advance 

 of the orbits. The extent of their different elements cannot be 

 determined. 



