1903.] 



AXD WIXDriPE OF THE AMEraCAX ^a'LTURE,S. 



391 



desceiading process of the laciymal, not so pronounced as in the 

 Condor, but more developed than in Gypagus, where it is indeed 

 vertical in direction. Another difference which allows of a closer 

 association of the Condor with the King Vulture than of either 

 with Cathartes, is the condition of the interorbital septum. In 

 both Sarcorhamphus and Gypagus there are two large vacuities, 

 the larger being in front. In Cathartes the septum is less per- 

 forated, the posterior vacuity alone being present — a tiny hole '■■'■ 

 representing the anterior vacuity. Pycraft has called attention to 

 a series of stages in the development of the attachment of the 

 maxillo-jugal bar. It appears to me that the facts observable tend 

 to suggest that Gypagus stands rather apai't from both Cathartes 



Text-fiff. 48. 



G-ypagus papa . 



Upper figure : insertion of maxillo-jugal (J), 

 Lower figure : mandible, viewed from behind. 



and Sarcorhamphus. In the former genus (text-fig. 48) the bar 

 divides only just before the insertion on to the maxilla. The upper 

 lamella is of large size, and, as in the two other genera, fits on to 

 a liollowed-out area of the maxilla. In Cathartes (text-fig. 47, 

 p. 390) and Sarcorhamphus (text-fig. 46, p. 390) the division of 

 the bar occui'S much further back. The upper lamella is certainly 

 larger than the lower bar, but it is relatively smaller than in 

 Gypagus. In Sarcorhamphus^ indeed, it is actually of the same 

 breadth as in Gypagus, though the skull of the Condor is twice 

 the size of that of the King Vulture. Fuithermore, the forward 



* This seems to bo not always present. It is not figured by Pyciaft. 



