206 



DE. P. CHALMEES MITCHELL ON THE 



ACCIPITRES. 



Gtpogeranid,e. — In Serpentar'ms reiitili corns (fig. 27) the duodenum is simple. 

 Meckel's tract presents first three narrow minor folds, and then expands into a nearly 

 circular portion like that in Cathartes, the axis being given by the middle mesenteric 

 vein which runs from a Meckel's diverticulum. Then follows a long supra-duodenal 

 loop, drained partially by a " bridging " vein. Posterior to this is a typical supra-csecal 

 kink, and then a pair of reduced caeca. The rectum is of moderate length and straight. 



Fig. 27. 



lutestinal Tract of Serpenlarius repfUivurns. Lettering as before. 



Vtilttjrid^. — Neophron percnopte^'us (fig. 28) and other Vultures which I have 

 examined are closely similar. The duodenum is an irregularly expanded loop. Meckel's 

 tract presents three distinct minor loops (numbered 1, 2, and 3 in the figure), which 

 reappear constantly in Falconiform birds ; tlien follows an axial loop bearing Meckel's 

 diverticulum, and then several long, rather irregular loops, the last of which is a typical 

 supra-duodenal loop with " bridging " vein. The caeca are vestigial, and above them lie 

 two supra-caical kinks drained by the rectal vein. The rectum is short and straight. 



