VISCERAL ANATOMY. 133 



omentum. This is confounded laterally with the mesenteries of 

 the colon. 



The great omentum communicates with the general peritoneal 

 cavity behind the stomach by an opening, the joramen of Winslow, 

 bounded by the vena portce, cava, pancreas and lesser curvature 

 of the stomach. 



It is then reflected over the small and large intestines, forming 

 their mesenteries, the ligaments of the bladder, broad ligaments 

 of the uterus, and then from the rectum and front of the bladder 

 is reflected to the superior and inferior abdominal wall, forming 

 the parietal layers. The inferior abdominal portion continues 

 forward and forms the suspensory ligament of the liver. The 

 superior abdominal portion passes beneath the kidney, giving it 

 support, and after forming the mesenteries is continued to the 

 diaphragm, as the upper layer of the suspensory and gastro- 

 hepatic ligaments. 



Structure. 



A basement membrane covered with flattened polygonal en- 

 dothelial cells. 



RESPIRATORY SYSTEM. 



In this system, the great process of oxygenation of the blood 

 takes place, as well as the throwing off of excrementitious sub- 

 stances, viz., carbonic acid gas, solids, etc. 



The air passages are from above, downward, the nasal fossa, 

 larynx, trachea, bronchi and lungs. 



For a description of nasal fossa, see special senses. 



LARYNX. 



The larynx is a cartilaginous box, being the organ of voice. Its 

 anterior opening is at the bottom of the pharynx, its posterior 

 continuous with the trachea. 



Structure. 



Five cartilages, twelve muscles, and a mucous membrane. 



Cartilages. 



Thyroid, cricoid and epiglottis, single ones and one pair, the 

 arytenoids. 



