muscle to the end of the oesophagus, passes for a short dis- 

 tance on to the wall of the stomach. The portion of the 

 section coming from the stomach is lined by a single layer 

 of columnar cells. A few imperfectly formed peptic glands 

 are also seen. Sketch the portion of the section showing 

 the junction of the stratified pavement and the single layer 

 of columnar epithelium with the underlying mucosa, as 

 seen under low power. 



(c) Cardiac End of the Stomach. 



Pieces from the cardiac end of the stomach of a dog were 

 hardened in absolute alcohol, embedded in paraffin, and sectioned. 

 The sections were fixed to cover glasses, and stained in the Ehrlich- 

 Biondi triple stain, dehydrated, and cleared in oil of bergamot and 

 xylol. Mount on balsam. 



Study first under low power. Observe the mucosa 

 with the cardiac glands, the muscularis mucosa, the fibrous 

 submucosa with the larger vessels, the muscular coat com- 

 posed of two or three layers of non-striped muscle, and the 

 peritoneal coat. Under high power the finer details are 

 mado out. The peptic glands are simple or branched 

 tubular glands, with short neck and comparatively long 

 secreting tubules. In the latter two kinds of cells are 

 found, the central, chief, or peptic cells, stained a faint 

 green color, and the parietal or oxyntic cells of Langley, of 

 oval shape and stained a reddish tinge. 



This section, and the sections of the pyloric end of the 

 stomach and of the small and large intestines are to be 

 sketched side by side in the spaces outlined for you on two 

 of the pages reserved for the drawings of this lesson. The 

 sketches are to be so made that the muscularis mucosa of 

 each of the four sections falls on the dotted line running 

 across the pages. The relative thicknesses of the several 

 coats should be shown as accurately as possible. Sketch 

 under low power. 



(d) Pyloric End of the Stomach. 



The tissue was taken from the pyloric end of a dog's stomach, 

 hardened in alcohol, stained in borax carmine, and embedded in 

 paraffin. Mount in balsam. 



