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PRINCIPLES OF VETERINARY SCIENCE 



and above the large colon, so it does not come in contact with 

 the walls of the cavity. The stomach is held in position mainly 

 by the pressure of the surrounding organs and by the esophagus. 

 Like other hollow viscera, it has three layers to the wall — the 

 mucous, the muscular, and the serous. The mucous layer is 



Fig. 24. — Thoracic and anterior abdominal viscera of ox; deep dissection. 

 Most of the rumen has been removed and the left wall of the reticulum cut away. 

 A., Left pulmonary artery; B., left bronchus; V. V. V., pulmonary veins; b. b., 

 bronchial lymph glands ;L.g., posterior mediastinal lymph gland ; D., termination 

 of duodenum ; F, rumino-reticular fold. (Sisson, Anatomy of Domestic Animals.) 



clearly divided into two parts by the margo plicatus (Fig. 22). 

 That which lies to the left contains no glands, is similar to the 

 lining of the esophagus, and is covered with thick stratified 

 epithelium. The glandular part is subdivided into three zones, 

 according to the types of glands which it contains, but no dis- 

 tinct lines of division exist. The narrow, yellowish-gray zone 

 next to the non-glandular portion contains the short, tubular 

 cardiac glands. Next to this lies a large mottled, reddish- 



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