The _intestine_ of mammals is always long and much coiled, though the length and consequent degree of coiling naturally varies. On the whole it is perhaps safe to say that it is shorter in carnivorous than in vegetable-feeding beasts. Thus the Paca has an intestine of 39 inches total length, while the Cat, an animal of about the same size, has an intestine which is only 36 inches long. A fish diet, however, to judge from the Seals, is associated with a long intestinal tract. The intestine is divisible in the vast majority of mammals into a small and a large intestine. The two are separated by a valvular constriction save in certain Carnivores; and in the majority of cases the distinction is also emphasised by the presence at the junction of a blindly-ending diverticulum, the _caecum_. This latter organ varies greatly in length, being very short in the Cat-tribe and exceedingly long in Rodents. Its size is, to some extent, dependent upon the flesh-eating or grass-eating propensities of the animal in which it occurs. One of the longest caeca is possessed by the Vulpine Phalanger, in which the organ is one-fifth of the length of the small intestine; while the opposite extremity is reached by _Felis macroscelis_, which has a small intestine one hundred times the length of the caecum. {63} [Illustration] FIG. 41.--Different forms of the stomach in Mammals. A, Dog; B, _Mus decumanus_; C, _Mus musculus_; D, Weasel; E, scheme of the Ruminant stomach, the arrow with the dotted line showing the course taken by the food; F, Human stomach. _a_, Minor curvature; _b_, major curvature; _c_, cardiac end. G, Camel; H, _Echidna aculeata_. _Cma_, Major curvature; _Cmi_, minor curvature. I, _Bradypus tridactylus_. _Du_, Duodenum; _MB_, coecal diverticulum; **, outgrowths of duodenum; +, reticulum; ++, rumen. _A_ (in E and G), Abomasum; _Ca_, cardiac division; _O_, psalterium; _Oe_, oesophagus; _P_, pylorus; _R_ (to the right in E and to the left in G), rumen; _R_ (to the left in E and to the right in G), reticulum; _Sc_, cardiac division; _Sp_, pyloric division; _WZ_, water-cells. (From Wiedersheim's _Comparative Anatomy_.)