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ANATOMY AND PHYSIOLOGY. 



tious food which they subsist upon, until all its useful particles can 

 be absorbed. In carnivorous animals again, the intestinal canal is 

 short, because the food is so highly nutritious, that digestion is 

 very quickly completed. From this pouch, then, the great gut 

 ascends in the right side, crosses over the belly below the stomach, 

 descends in the left side, forms a twist like the letter S, and then 

 turns into the pelvis to open outwardly at the anus. It is called 

 the colon. 



It has already been stated, that the nourishing part of the food, 

 the chyle, is absorbed from the intestines by an infinity of small 

 vessels, having a close affinity to veins. Their structure is very 

 like that of veins, and they are provided with valves, which prevent 



Lucteals, Mesentery Glands, and Thoracic Duct, running up the spine and emptying its contents, 

 the purified chyle, into the left subclavian vein, and thus mixing with the blood 



r ideal vessels emerging from the mucous surface of the intestines. 2. First order of mesen- 

 teric glands. 3. Second order of mesenteric glands. 4. The great trunks of the lacteals. emerg- 

 ing from the mesenteric glands, and pouring their contents into 5. The receptacle of the chyle. 

 6. The great trunks of the lymphatic or general absorbent system, terminating in the receptacle 

 of the chyle. 7. The thoracic duct. 8. Termination of the thoracic duct at 9. The angle formed 

 by the union of the internal jugular vein with the subclavian vein. 



