THE BONY FRAMEWORK 



its bend, and the larynx is hung from it as from a hook. To 

 this bone are attached muscles which move the tongue. The 

 hyoid, like the kneepan, is not connected with any other bone. 



Experiment 8. To locate the hyoid bone. With the neck resting in 

 its natural position, gently grasp the front of the throat with the 

 thumb and forefinger just above 

 the "Adam's apple." The hyoid 

 bone can be plainly felt on a level 

 with the lower jaw and about one 

 inch and a half behind it (Fig. 1 73). 



THE BONES OF THE 

 TRUNK 



38. The Trunk and its Two 

 Cavities. The trunk is that 

 part of the body which sup- 

 ports the head, and to which 

 the arms and the legs are 

 attached. It has two impor- 

 tant parts, or cavities. 



The upper part, called the 

 thorax, or chest, is like a basket or cage of bone. It is 

 formed by the breastbone in front, the ribs and a part 

 of the backbone behind. It contains the lungs and the 

 heart. 



The lower part, or abdomen, holds the stomach, liver, 

 intestines, kidneys, and other important organs. 



The chest and abdomen are separated by a muscular 

 partition known as the diaphragm, which serves as the chief 

 muscle in breathing. 



39. The Bones of the Trunk. The principal bones of the 

 trunk are those of the spine, the ribs, and the hips. 



FIG. 17. The Top of the Skull, 

 showing the Sutures. 



