NO. 9 



NEW RIVER-DOLPHIN FROM CHINA — MILLER 



Lateral Aspect 



(Plates 4 and 5) 



Lipotcs 



Crest turned abruptly upward over 



orbit. 



Length of orbit nearly half that of 

 temporal fossa. 



Glenoid process strongly curved 

 forward. 



Squamosal tapering anteriorly. 

 Lateral groove on beak well de- 

 fined, but wide and shallow. 



Iiiia 



Crest not turned abruptly upward 

 over orbit. 



Length of orbit scarcely one-fifth 

 that of temporal fossa. 



Glenoid process not strongly 

 curved forward. 



Squamosal enlarged anteriorly. 



Lateral groove on beak narrow, ill 

 defined. 



Ventral 

 (Plates 6 



Distance from last tooth to maxil- 

 lary notch much greater than width 

 of beak at last tooth. 



Beak narrowed between toothrow 

 and maxillary notch as in Pontistes, 



Keel flattening out at level 45 mm. 

 behind last tooth. 



Edge of basal wing deeply notched 

 so that pterygoid is nearly or quite 

 cut off from contact with basi- 

 sphenoid. 



Depression on squamosal at inner 

 side of glenoid area sharply defined, 

 narrowed in front. 



Aspect 

 and 7) 



Distance from last tooth to maxil- 

 lary notch less than width of beak 

 at last tooth. 



Beak not narrowed betwen tooth- 

 row and maxillary notch. 



Keel flattening out at level of last 

 tooth. 



Edge of basal wing entire ; ptery- 

 goid broadly in contact with basi- 

 sphenoid. 



Depression on squamosal at inner 

 side of glenoid area ill defined, wider 

 in front than behind. 



Occipital 

 (Plate 



Supraoccipital area wider than 

 high, essentially flat; a distinct 

 median ridge extending from lamb- 

 doid crest nearly to foramen magnum. 



Area of foramen magnum about 

 half that of one supraoccipital. 



Two deep furrows in region be- 

 tween paroccipital process and gle- 

 noid process (clearly shown on right- 

 hand side of figure). 



Aspect 

 8) 



Supraoccipital area higher than 

 wide, each bone noticeably convex 

 both vertically and laterally ; a median 

 furrow extending from near foramen 

 magnum to above middle. 



Area of foramen magnum about 

 one-fourth that of one supraoccipital. 



Only one deep furrow in region be- 

 tween paroccipital process and glenoid ' 

 process. 



