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A MANUAL OF PHYSIOLOGY 



o C, for example, being felt only as cool, and not as cold. The 

 outer limit of this region is the line at which the temperature 

 of o C. is first felt as we work inwards from the normal skin to 

 yield the sensation of cool instead of cold. Similarly, the outer 

 limit of thermo-hypoaesthesia can be determined by using a high 

 temperature (50 C.). It is the line at which the sensation of 

 hot yielded by the normal skin gives place to the sensation of 



SJ 



FIG. 430. MIDDLE CUTANEOUS : LEFT THIGH (TROTTER AND DAVIES). 



Twenty-one days after section. Results of examination with temperature of 

 o C. On spots marked stimulus was felt as cold ; on spots marked o it was 

 felt as cool. The blank area is that of thermal anaesthesia. The continuous 

 outline marks the limit within which there was anaesthesia to the camel's-hair 

 brush. 



warm. The two boundaries correspond closely when allowance 

 is made for the separate grouping of cold and warmth spots on the 

 normal skin. 



The investigation of the sensibility of the skin areas for painful 

 stimuli is complicated by the fact that during a certain period, 

 from about the second to the sixth week after division of the 



