312 University of California Publications. [Geology 



Measurements of Skull. 



Width across postero-ventral points of postauditory prominences.. 70. mm. 



Width across postorbital processes 94. 



Width through masseteric notch 69. 



Least interorbital width of frontal region 55.3 



Highest point of crown above sphenoidal rostrum 57.2 



Depth of foramen magnum 14.3 



Greatest transverse diameter of foramen magnum 12.4 



Sagittal diameter of occipital condyle 7. 



Transverse diameter of occipital condyle 8.2 



Length from nuchal tubercle to anterior margin of lachrymal ... 99.3 

 Diameter of orbit from postfrontal process to posterior point of 



lachrymal 45. 



Diameter of orbit from postfrontal process to ventral point of 



lachrymal 52.5 



PECTOEAL ARCH. 



There are in the University collection the coracoids, sternum 

 and furcula of a raptorial bird of gigantic size which probably 

 represent Teratornis and are therefore provisionally described 

 in this connection. 



The sternum (no 11190) shows three points of divergence 

 from the Recent raptorial type (figs. 6 and 7). First: its length 

 is greatly reduced until it becomes less than the extreme breadth. 

 Second : the anterior region is expanded until the manubrium 

 becomes a wide, slightly produced mound, excavated at its sum- 

 mit in an open, gentle curve which separates the coracoidal 

 fossae by a distance of 23 mm. Third : the hyosternal processes 

 are developed forward and outward till the anterior and the 

 lateral margins of the sternum both become strongly concave. 

 Since, however, the rib articidations come to the end of the hyo- 

 sternal processes, the condition might be more properly consid- 

 ered an excavation of the anterior and the lateral borders by a 

 prolongation of the hyosternal processes. 



The rib articulations are but five, a number more cathartid 

 than falconid. The general concavity of the sternum is similar 

 to that of Recent Raptores. 



The hyosternal fossae occupy the entire anterior part of the 

 hyosternal processes, but are not prolonged backward along the 

 costal articulations. Owing to the transverse extension of these 

 processes the fossae then become very much extended laterally, 

 but very narrow in their anteroposterior dimensions (fig. 6). 



