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Show i896.] INTESTINAL TRACT OF BIRDS. 143 three parts. In Eudyptes chrysocome 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. PROCELL ARIIFORMES . The Northern Petrel (fig. 7) presents several interesting modifications of the type. The duodenum is compound, the first part being twisted round the small gizzard, the second part forming a Fig. 7. Fulmarus glacial is; intestinal 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 caeca, is expanded into two subsidiary loops. ClCONIIFORMES. The birds in this group that I have examined have all departed similarly from the type. The whole intestine is enormously elon- |