100 HANDBOOK OF PHYSIOLOGY. 



and subdivides to form a series of arborizations, more or less distinct 

 and destined for the different parts of the corpuscle. The terminal ar- 

 borizations occupy the central part of the corpuscle, and are surrounded 

 by a great number of marginal cells. The touch, or tactile corpuscles 



Fig. 112. Papillae from the skin of the hand, freed from the cuticle and exhibiting tactile cor- 

 puscles. A. Simple papilla with four nerve-fibres; o, tactile corpuscles; 6. nerves with winding 

 fibres c and e. B. Papilla treated with acetic acid; a. cortical layer with cells and fine elastic fila- 

 ments; 6, tactile corpuscle with tran verse nuclei; c, entering nerve with neurilemma or perineu- 

 rium ; d and e, nerve-fibres winding round the corpuscle. X 350. (Kolliker.) 



of Meissner, have been regarded at one time as epithelial, at another 

 time as nervous, but they are to-day proved to be mesodermic cells, and 

 differentiated for the special purpose of the sense of touch (Dejerine). 



Fig. 113. End-bulb of Krause. , Medullated nerve-fibre; 6, capsule of corpuscle. 



3. The Corpuscles of Krause or End-Bulbs. These exist in 

 great numbers in the conjunctiva, the glans penis, clitoris, lips, skin, 

 and tendon of man; they resemble the corpuscles of Pacini, but have 

 much fewer concentric layers to the corpuscle, and contain a relatively 

 voluminous central mass composed of polyhedral cells. In man these 



