SQ Mammalia. Digestive System. 



The GEsophagus is of small area in the largest species of Cete. 



extends beyond the diaphragm in Cercopithecus, the small 

 Platj'rrhines, and Cheiromys [\ inch), of iheQuadrumana ; in most 

 Insectivora, Rodentia, and Uijracoidea ; in the DidelphidaB and Ma- 

 cropidse (M. major. 5 in.) of the Marsupialia ; and in the Monotre- 

 matous Ornithorhyncus. 



has in Leo ( ? all Felidse) {Sectorialia) a third layer of longi- 

 tudinal fibres applied to the inner side of the circular ones at the 

 terminal part of the (Esophagus. 



has in Leo (? all Felidae) (on account of the special arrangement 

 of the muscular fibres) the lining membrane puckered up into numer- 

 ous narrow alternating transverse rugae. A similar structure is 

 present in Didelphys Virginiana (Marsupialia). 



in ^quus [Perissodactyla) presents a more or less large sickle- 

 shaped fold, developed close to the Cardiac orifice of the stomach, 

 which prevents the return of food, so that the Horse cannot vomit. 



has a sheath of striated muscular fibre. Several different Orders, 

 or Families of Mammalia have a sheath of striated muscular fibre 

 extending all along the CEsophagus, to or even on the Cardia, as may 

 be well seen in Euminants, Rodents, Bears, and many others : it 

 may, however, stop short of the Cardiac end of the (Esophagus, e.g. 

 in Man, Quadrumana, Felidae, the Horse, and many others.* 



14. The Stomach. 



{a) is Simple in 



Bimana, in which the Cardiac pouch is relatively small, and the 

 (Esophagus enters near the Cardiac end, thus admitting of an ex- 

 tensive lesser curvature. 



In most Qtcadnwiana, e.g. the tail-less Apes, the Lemurida? (in 

 which last the Cardiac portion is large), and Cheiromys, in which the 

 Stomach is subglobular. 



In nearly all Insectivora^ the Cardiac and Pyloric orifices being 

 approximate. 



In the Insect-eating Cheiroptera. 



In the Sectorialia, where the Cardia and Pylorus are generally 

 wide apart; the * blind sac' is of small extent, and the Pyloric end 

 is bent abruptly and closely upon the middle of the stomach. The 



* Gulliver. 



