INTESTINAL TRACT OF B1EDS. 



Fig. 28. 



207 



Intestinal Tract of Neophron percnopterus. 

 I, 2, 3, three anterior loops of Meckel's Tract. Other lettering as before. 



(1) Gypaetincf. Gypohierax angolemis (fig. 29) displays an alimentary tract extremely 

 like that of the true Vultures. The duodenum is simpler, being a long, narrow loop. 

 Meckel's tract hegins with three distinct minor loops (1, 2, and 3) ; then follows an axial 

 loop, with Meckel's diverticulum, and the remaining part of the tract, including the 

 supra-csecal kinks and the vestigial caeca, is precisely as in the Vultures. 



(2) Polyborince. In Polyborus brasiliensis (fig. 30), the Brazilian Caracara, the 

 duodenum forms a long, narrow loop, which is wound into a spiral. Meckel's tract 

 consists of a set of small loops arranged very symmetrically, the axial loop as usual 

 hearing a Meckel's diverticulum. There is a well-formed but single supra-caecal kink in 

 the normal position, and anterior to that a supra-duodenal loop. The caeca are vestigial, 

 and the rectum is short and straight. 



(3) Accipitrinee. In Circus c'meraceus (fig. 31) is to be found what may be regarded as 

 a central condition for the Falconidae. The duodenum is a large, very wide loop. 



32* 



