280 OUTLINES OF EQUINE ANATOMY. 



and then again forwards, and forming a covering for part 

 of the double colon, produces a peculiar cavity of serous 

 membrane, connected to the main cavity by a channel up 

 against the anterior mesenteric artery, which has received 

 the name of foramen of Winslow. In the gastro-colic or 

 or omentum major, we sometimes find much fat. By 

 butchers it is termed the " caul.'' 



The stomach of the horse presents a rounded cul-de-sac 

 at its left extremity, more marked than in most other 

 animals. It has a muscular and a mucous coat in addition 

 to the peritoneal already described. The muscular coat, 

 centrally placed between the serous and mucous layers, 

 presents three lasers of fibres : longitudinal, most marked 

 along the lesser curvature, continuous with those of the 

 oesophagus and duodenum at their extremities ; oblique, 

 which predominate at the left extremity ; and circular, con- 

 tinuous with those of the oesophagus and duodenum, ex- 

 tending over the whole surface of the viscus, and which 

 centrally by their contraction seem sometimes to practically 

 divide it into two compartments. 



The mucous layer is divided into two parts, cuticular 

 and villous. These two portions present a sharp line of de- 

 marcation, which is sigmoid. The former occupies about the 

 left third of the inner surface of the stomach, and is ana- 

 logous with the mucous membrane of the three first com- 

 partments of the stomach of the ruminant, for it is directly 

 continuous with that of the oesophagus, being whiter and 

 more firm than that forming the villous portion, which is 

 reddish in colour, slimy in nature, and occupies the left 

 two thirds of the stomach, being continuous through the 

 pyloric opening with that of the duodenum. Upon exa- 

 mination under the microcsope we may distinguish in this 

 portion glandular follicles or peptic glands, the deeper 

 portions of which are lined by spheroidal epithelium, and 

 which secrete the gastric juice, in addition to those mucous 

 follicles lined by tessellated epithelium, which secrete 

 mucus, and are apparent also in the cuticular portion. 

 To the cuticular portion we sometimes find bots (oestrus 

 equi) adhering, rarely to the villous. The left extremity 

 of the stomach comes in apposition with the pancreas, dia- 

 phragm, left kidney, and left pre-renal capsule. All the 

 branches of the coeliac axis supply this organ ivith blood. 

 The gastric (centrally situated) runs direct to the centre 



