XVI.] STOMACH. GASTKIC JUICE. MILK. 1-71 



from the upper part of the oesophagus show 

 no unstriped fibres. 



b. The submucous tissue contains small serous 

 and mucous glands (of. Lesson xv.). Each of 

 these consists of a duct, dividing and ending 

 in dilatations, the alveoli. 



c. Traces of the muscularis mucosoe. 



d. The papillse of the mucous membrane. 



e. The epithelium forming a layer several cells 

 deep, the deeper being columnar or sphe- 

 roidal, the superficial cells flattened (cf. Epi- 

 dermis, Lesson xxiv.). 



C. Gastric juice, 

 1. Artificial Gastric Juice. 



a. Tear off the mucous membrane from the 

 stomach of a mammal, cutting away the 

 pyloric region (the stomach of a pig obtained 

 from the butcher's will serve). Mince it 

 finely. Put it in a flask with two hundred 

 times its bulk of hydrochloric acid '2 p.c, 

 and place the flask in a water bath at about 

 40° 0. After some hours a considerable part 

 will be dissolved. Decant, and filter the 

 decanted fluid. A solution of pepsin in 

 hydrochloric acid will be obtained; it will, 

 however, contain a considerable quantity of 

 peptone. 



b. Mince another gastric mucous membrane; 



