426 



THE SEIN. 



occupying the principal part of the interior of the papilla, 

 and termed a touch-corpuscle (fig. 106). The nature of this 

 body is obscure. Kolliker, Huxley, and others, regard it as 

 little else than a mass of fibrous, or connective tissue, 

 Fig. 106.* 



surrounded by elastic fibres, and formed, according to 

 Huxley, by an increased development of the neurilemma 

 of the nerve-fibres entering the papilla. Wagner, how- 

 ever, to whom seems to belong the merit of first fully 

 describing these bodies, believes that, instead of thus 

 consisting of a homogeneous mass of connective tissue, 

 they are special and peculiar bodies of laminated structure, 

 directly concerned in the sense of touch. They do not 

 occur in all the papillae of the parts where they are found, 

 and, as a rule, in the papillae in which they are present 



* Fig. 106. Papillae from the skin of the hand, freed from the cuticle 

 and exhibiting the tactile corpuscles. Magnified 350 diameters. 



A. Simple papilla with four nerve-fibres : a, tactile corpuscle ; b, nerves. 



B. Papilla treated with acetic acid : a, cortical layer with cells and fine 

 elastic filaments ; b, tactile corpuscle with transverse nuclei ; c, entering 

 nerve with neurilemma or perineurium ; d, nerve-fibres winding round 

 the corpuscle, c. Papilla viewed from above so as to appear as a cross 

 section : a, cortical layer ; b, nerve-fibre ; c, sheath of the tactile cor- 

 puscle containing nuclei; d, core (after Kolliker). 



