18 



University of California Publications. 



[Geology 



appears just posterior to the tuberosity cannot be definitely outlined. 

 The depression between the head proper and the hypotarsus is a very 

 broad shallow and smooth area marked off on all its borders by raised 

 ridges. In none of the other species does this condition appear so 

 entirely fulfilled. 



Table of Measurements. 



Tarso-metatarsus. 



Total length 149.6 mm. 



Greatest transverse diameter of head 34.5 



Greatest sagittal diameter of head 27.00 



Greatest transverse diameter through trochleae 34.6 



Greatest transverse diameter of middle trochlea 13.2 



Greatest sagittal diameter of middle trochlea 19. S 



Least transverse diameter of shaft 15.8 



Sagittal diameter at middle of shaft 12.3 



Width of partition between proximal foramina 2.9 



Transverse diameter of pit into which the proximal fora- 

 mina open - 7.0 



Longitudinal diameter of the same 9.0 



A consideration of the large size and the cathartine affinities 

 of Teratornis merriami naturally raises the question of possible 

 assignment of the present series to that species. There are 

 several considerations which seem to the author to render such 

 procedure inadvisable. The discrepancy in size between 

 Sarcorhamphus gryphus and Teratornis merriami as represented 

 by the skull and the pectoral girdle is greater than is exhibited 

 by the tarsi at hand. It seems far from logical that Teratornis 

 with its powerful raptorial beak should have had especially weak 

 feet, since the food of the bird must have been such as to demand 

 its coming to earth or to perch at least while the prey was being 

 devoured. The throwing of the large body into the air upon 

 resuming flight would seem to demand a development of the 

 pelvic limb at least proportional to that of the existing condors. 

 If the foot of Teratornis were in harmony of character with the 

 powerful predatory beak, it would be prehensile and offensive. 

 The shank would under those circumstances be very stout, and 

 deeply concave on its posterior face, for the flexor tendons and the 

 transverse plantar arch would be more pronounced. In the face 

 of thus much evidence, it seems improbable that no. 12599 could 

 belong to Teratornis merriami. 



