18 INTRODUCTION 



dorsal cavity is sectioned in a longitudinal direction 

 it will show, above, the cranial cavity, and below, 

 the spinal cord, the former containing the brain and 

 its membranes, the latter the spinal cord and its 

 membranes. 



The ventral cavity includes the space within the 

 trunk and in front of the spinal column. Its walls 

 consist of skin, fascia, and muscles reinforced by bony 

 arches, the ribs, and the pelvic bones. The ventral cavity 

 is subdivided by a musculomembranous wall, the dia- 

 phragm, into an upper cavity called the thorax, and a 

 lower one, the abdomen. The former contains the organs 

 of respiration the lungs and the heart, covered by their 

 membranes, also the great bloodvessels leading from 

 the heart, and the esophagus (gullet), which conveys 

 food from the pharynx to the stomach by passing 

 through the diaphragm. The abdomen contains the 

 remaining portions of the tube (alimentary canal), 

 which receives the food from the esophagus and ends 

 in the lower part of the cavity called the anus; also 

 the organs of secretion liver, pancreas, spleen, etc.; 

 excretion kidneys, bladder, etc., and reproduction in 

 the female. 



The appendicular portion of the body consists of four 

 extremities two upper and two lower limbs. The 

 upper limbs consist of bones held together by liga- 

 ments, and covered with muscles, tendons, fascia, and 

 skin. The lower limbs have the same construction as 

 the upper, but the joints are not so capable of move- 

 ment. For example, the shoulder and elbow are freely 

 movable, as compared with the hip. 



The study of anatomy is divided into the following 

 branches : 



Osteology: the anatomy of the bones. 



Syndesmology : the anatomy of the joints. 



Myology: the anatomy of the muscles. 



Angiology: the anatomy of the bloodvessels. 



Neurology: the anatomy of the nerves. 



