189^.] iNtESIINAi TBACT OF BIHDS^ 143 



three parts. la Eudyptes chrysocmie the duodenum forms a 

 subsidiary system of loops ; in Aptenodytes pennanti a spiral, bearing . 

 a convergent resemblance to the duodenum of the long-gutted Sea- 

 Eagles. The circular loop is thrown into an enormous series of 

 minor folds, about the middle of which, but in a position similar 

 to that in the Divers, occurs the yolk-duct vestige. The last two 

 loops are supplied from the duodenal vessel. The posterior part 

 of the gut is quite like that of the Diver, although the caeca are 

 still further reduced. • ■ 



Phocbllariii'oemes. 



The Northern Petrel (fig. 7) presents several interesting modifi- 

 cations of the type. The duodenum is compound, the first part 

 being twisted round the small gizzard, the second part forming a 



Pig. 7. 



Y 



Fulmariis glacialis ; iutestinal tract, x, short-circuiting vessel cut across. 



long loop containing the pancreas in the typical fashion. The 

 circular loop is drawn out into a number of straight narrow loops, 

 on the fourth of which occurs the vestige of the yolk-duct. The 

 last loop is drained partly from the normal source and partly by a 

 short-circuiting vein from the duodenum. The posterior part of 

 the intestine is like that of Colymbus and the Penguin, with the 

 exception that, as in the Sea-Eagle, the portion of the gut supplied 

 by the posterior mesenteric vessel, but anterior to the origin of the 

 cesca, is expanded into two subsidiary loops. 



CiCONIIFOEMES. 



The birds in this group that I have examined have all departed 

 similarly from the type. The whole intestine is euorinously elou- 



