286 



THE ALIMENTARY TRACT, ETC. 



more nearly resemble oesophageal glands. At the same point the 

 mucous membrane is thinner than either in front or behind. In 



Fig. 188. 



Transverse section through the 

 mucous membrane of the 

 pyloric end of the stomach 

 of Rana esculenta. After 

 Partsch. (Obj. II, Syst. 7, 

 Hartnack. ) 



the same way an intermediate zone exists 

 between the typical glands of the fundus 

 and pylorus of the stomach.] 



In both oesophagus and stomach the 

 mucous membrane is thrown into longi- 

 tudinal folds when the organs are empty. 

 The epithelium of the surface of the 

 oesophagus is mostly ciliated, and possesses 

 numerous goblet cells; according to Klein 

 the cells are not set vertically on the sub- 

 jacent submucosa, but obliquely. 



[The epithelium of the surface of the 

 stomach is, at least in part, ciliated (Re- 

 geczy, Trinkler, and others), and has nu- 

 merous goblet-cells (Schultze, Heidenhain, 

 Bleyer, Eimer, Oedmonson, and others).] 



(5) [The nerves of these organs, accord- 

 ing to Gonjaew, contain both medullated and non-medullated fibres, 

 which have nerve-cells attached to them. From these fine branches 

 pass, either with the blood-vessels or alone, to the mucous coat, 

 losing their medulla on the way. In this course they inosculate 

 very freely, and are then distributed as very fine, beaded fibrils to 

 the glands and epithelium, which are very richly supplied.] 



(6) [The blood-vessels and lymphatics very closely resemble the 

 corresponding structures in the small intestine (p. 290) ; the blood- 

 vessels form a rich anastomosis in the submucous membrane; the 

 lymphatics are arranged in two systems, one under the serous coat, 

 and a larger system in the mucous and submucous coats. The 

 oesophagus lies free in a peri-oesophageal lymph-sac (Robinson).] 



C. The Small Intestine. 



a. General description. The small intestine commences behind 

 the middle of the abdomen at .the pyloric end of the stomach, from 

 which it is marked off by a slight constriction. The first portion 

 of the small intestine is the duodenum (Figs. 1 84 and 1 94 Du) ; by 

 means of an abrupt turn it winds directly forwards, parallel to the 

 long axis of the stomach ; the pancreas is placed in the loop so 

 formed. 



The whole of this portion of the intestine, together with the 



