554 



ZOOLOGY 



SECT. 



ridges, which are capable of closing together in such a way as to 

 convert the groove into a canal. The mucous membrane of the 

 psalterium (d) is raised up into numerous longitudinal leaf-like 

 folds. The abomasum (e), smaller than the rumen, but larger than 

 the reticulurn, has a smooth vascular and glandular mucous mem- 



A 



Oe 



FIG. 1210. Different forms of the stomach in Mammals. A, Dog ; B, Mus decumanus ; 

 C, Mus miisculus ; 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, b, c, 

 muscles on inner side ; d. Camel ; H, Echidna aculeata ; /, Bradypus tridac- 



tylus. A. (in E and (?) abomasum ; Ca. cardiac end ; Cma, greater curvature ; Cmi, 

 lesser curvature ; Du. duodenum ; MB, caecum ; O, psalterium ; Oe. oesophagus ; P. 

 pylorus ; R. (to the right in Fig. E), tf. rumen ; R (to the left in Fig. E), t, reticulum ; 

 Sc. cardiac division ; Sp, pyloric division ; WZ, water-cells ; * * duodenal pouches. 

 (From Wiedersheim's Comparative Anatomy.) 



brane. The oesophagus opens into the rumen close to its junction 

 with the reticulum. The herbage on which the Ruminant feeds 

 is swallowed without mastication, accompanied by copious saliva, 

 and passes into the rumen and reticulum, where it lies until, having 

 finished feeding, the animal begins ruminating or chewing the 



