554 THE INTESTINAL CANAL, BY E. KLEIN AND E. VERSON. 



into the circular layer of the muscularis mucosse of the right half 

 of the stomach. The external fasciculi of the longitudinal 

 layer extend directly as such into the right half of the stomach ; 

 the internal fasciculi, however, decussate with the correspond- 

 ing ones of the right half, and partly penetrate between the 

 fasciculi of the circular layer. 



The muscularis externa also increases considerably in thick- 

 ness towards the fold, attaining its maximum at its base, and 

 then gradually diminishing. 



The tubular glands of the right half of the stomach are here 

 also at first short, and lined by columnar epithelium, which, 

 however, is soon replaced by rounded strongly granular pepsine 

 cells, so that the columnar epithelium of the surface only 

 penetrates as far as the upper fourth of the tubes. 



The muscularis mucosse of the right half of the stomach is 

 thinner than that of the left, the fasciculi decussate to a con- 

 .siderable extent, but are here and there divisible into an 

 internal circular and an external longitudinal layer. 



The proportion of smooth muscular fibres which are given 

 off into the mucous layer is here also considerable. 



Numerous ganglia are situated on the nerves lying between the 

 circular and longitudinal layers of the external muscular tissue. 



In BIRDS the laminated pavement epithelium of the oeso- 

 phagus ceases at the commencement of the glandular stomach 

 with a dentated border, and is replaced by a simple layer of 

 cylindrical cells. 



The flask-shaped and, at their extremities, slightly lobu- 

 lated glands of the mucous layer of the oesophagus, which have 

 gradually augmented in number from above downwards, cease 

 at the line where the columnar epithelium commences; and the 

 muscularis mucosse lying external to the mucosa, which di- 

 minishes in thickness where the oesophagus is continuous with 

 the glandular stomach, becomes, in consequence of the disap- 

 pearance of the loose submucous tissue, applied as a longitudi- 

 nal muscular layer to the muscularis externa, so that it appears 

 to form a single layer with this. In the lowermost portion of 

 the oesophagus more or less sharply defined lymph follicles 

 appear, which are either situated on the outer side of the 

 glands, or externally between these nearly to the epithelium. 



