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STUDIES IN ADVANCED PHYSIOLOGY 



foot and occasionally elsewhere, as in tendons and liga- 

 ments, or (especially true of the cat) in the mesentery. A 



Fig. 149. A PACINIAN CORPUSCLE FROM THE CAT'S MESENTERY. (After Ranvier.) 

 n, nerve; n', its continuation through the core m; a, termination of nerve in distal 

 end; d, c t coats or capsules; /, a channel for the nerve. 



Pacinian corpuscle is made up of a body of connective tissue 

 which shows quite a number of concentric rings. These 

 rings are really capsules. If one were to imagine a great 

 number of egg shells placed one within another and the 

 space between the contiguous egg shells filled with a little 

 liquid the analogy to the Pacinian corpuscle would be appar- 

 ent. In the center of these concentric capsules there is a 

 soft core in which a nerve fiber ends. 



2. The tactile cells. The tactile cells seem nothing more 

 than specialized cells of the lower layers of the epidermis. 

 In regions of the skin where sensation is very acute there 

 are found near the Malpighian layer certain cells which 

 seem to stain more deeply, are larger, more oval and more 

 granular than the ordinary epidermal cells. Delicate nerve 

 fibers can be traced to them which, according to some ob- 

 servers, end in networks which invest these tactile cells like 



