INTRODUCTION. xx i x 



portions separated by a well-marked constriction, and there are many 

 permanent folds in the pylorus. Generally, the small intestine is nearly 

 six or seven times the length of the large intestine, which is about as 

 long as the body. The length is increased by domestication in the Doo-s, 

 as in various other beasts. The small intestine is lined with lono- 



O' 



filiform villi. Peyer's patches are usually small and confined to the 

 middle of the intestine. The caecum is a moderate-sized, cylindrical 

 body, rounded at its end, and in the great majority of species curiously 

 contorted (fig. 13). In some species, however, as in C. jubatus, C. 

 cancrivorus, C.azara, C. procyonoides, and Icticyon venaticus (fig. 14), 

 it is almost or quite straight. 



The liver has an undivided left lateral lobe, and slightly smaller left 

 central one, compared with that of the Cat, and a very much smaller 

 right central lobe as regards that part of it which is placed on the right 

 side of the gall-bladder. The right lateral lobe, however, is much 

 larger. The caudate lobe is also relatively larger, and the Spigelian 

 lobe is divided into two lobules by a notch*. 



The brain shows four generally distinct and regular gyri surrounding 

 the short, nearly vertical Sylvian fissure. The first and second gyri have 

 their limbs anterior and posterior to the Sylvian fissure nearly equal. 

 The parietal (often called the " middle lateral ") gyrus has its posterior 

 limb broad and bifurcate. The sagittal gyrus (often called the " supe- 

 rior lateral gyrus ") is single. The hippocampal gyrus is divided from 

 the sagittal one by the junction of the calloso-marginal sulcus with the 

 largely developed crucial sulcus. The crucial sulcus, so characteristic 

 of the Carnivoraf, is very plainly marked (figs. 15 & 16). 



Some individual variation exists as to the extent of the bifurcation of 

 the parietal gyrus (m], and the separation between the first and second 



* In C. procyonoides the Spigelian lobe is very large, and various small differences 

 exist in different species. See Proc. Zool. Soc. 1878, pp. 374 and 375, and 1880, 

 p. 74. 



t For further information on this subject, see our paper in the ' Journal of the 

 Linnean Society,' vol. xix., Dec. 18, 1884, " Notes on the Cerebral Convolutions of the 

 Carnivora." 



