428 



THE BODY AT WORK 



skin which do not give the smarting sensation even though 

 the horsehair be pushed until it doubles up. 



Testing now for sensitiveness to cold with a cold blunt metal 

 point, " cold-spots " can be mapped on the skin. If the metal 



COT*. 



Medullary Sheath. 



'Perineufium. 

 \ -Endoneurium,. 



FIG. 43. PACINIAN CORPUSCLE. 



These organs are especially numerous in the neighbourhood of tendons and ligaments. They 

 are also present beneath the skin of the hands and feet. Their capsules are formed of a 

 great number of concentric lamellae of connective tissue, enclosing lymph-spaces. Within 

 the capsule is a core of finely granular substance, which also shows a tendency to a lamellar 

 disposition. The structure of these relatively large sense-organs is highly suggestive of 

 sensitiveness to pressure, traction, or rubbing. 



is warmed to about 50 C., " heat-spots " are found. The 

 different kinds of spot are very irregularly distributed. They 

 may coincide, or overlap, or leave blank spaces. Their relative 

 abundance varies. In some regions touch-spots, in others cold- 



