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INTRODUCTION TO NEUROLOGY 



Under the hairless parts of the skin there are special tactile bodies, such 

 as Meissner's corpuscles. These are generally found in the deep layer of 

 the skin (dermis) and in the underlying tissues, either as free skein-like 

 terminal arborizations of cutaneous nerves or as similar more elaborate 

 endings enclosed in connective-tissue capsules. Figures 24 and 25 illustrate 

 the most highly differentiated form of these endings, the Meissner cor- 

 puscles. Merkel's corpuscles (Fig. 26) are probably simpler organs of this 

 system. 



Stratum 

 corneum 



Stratum lucidum 



Stratum 

 _.- ?7 granulosum 



Blood-vessels 

 and nerves 



Fig. 24. Section through the human skin, illustrating the four layers 

 of the epidermis and the papillae of the dermis or corium. A corpuscle of 

 Meissner is seen within one of the dermal papillae. (From Cunningham's 

 Anatomy.) 



All forms of cutaneous sensibility (touch, temperature, and pain) when 

 studied physiologically are found to be localized in small areas or sensory 

 spots, each of which has a specific sensibility to one only of the cutaneous 

 sensory qualities. The intervening parts of the skin are insensitive. An 

 immense amount of physiological and clinical observation has been devoted 

 to the analysis of cutaneous sensibility, including the experimental division 



