TOUCH. 



921 



abdominal aorta and of the coccygeal gland, in the pancreas, on the pericardium, 

 at the side of the knee of the facial nerve, on the back of the penis and of the 

 clitoris, as well as in the mesocolon of the cat. Numerous connective-tissue 

 capsules, separated from one another by fluid, like the layers of an onion, surround 

 the homogeneous central bulb, which is filled with neuroplasm and is lined 

 by flat epithelial cells. The lamellae of the corpuscle are formed by hypertrophy 



Bulbous swelling of the axis- cylinder. 



Axis-cylinder. 



Concentric layer.-- 



Medullated nerve-fibe 



FIG. 333. Vater-Pacinian Corpuscle. 



of Henle's layer of the nerve-fiber, and are composed of nucleated, flat cells. 

 The medullated nerve-fiber, which enters the pedicle, loses its myelin-sheath, 

 and its sheath of Schwann, and terminates as an axis-cylinder either in a single 

 or in a bifurcated extremity, with a slight terminal enlargement, the end-bulb, 

 within which each nerve-fibril ends in a most delicate terminal nodule. 



Krause's longitudinal end-bulbs (Fig. 335) are found in the conjunctiva of 



Cells from which thr 

 end-bulb is formed. 



Sheath with nucle 



.Centrifugal nerve. 



FIG. 334. Spherical End-bulb in the Human Conjunctiva (Longworth). 



the eyeball, on the floor of the mouth, at the margin of the 

 lips, in the nasal mucous membrane, on the epiglottis, on 

 the fungiform and circumvallate papillae, on the glans 

 penis and clitoridis, in the tendilemma, in the tendons, 

 on the sole of the foot in man, on the plantar surfaces of 

 the toes (porpoise), on the ear and trunk (mouse) and in 

 the wing of the bat. They are from 0.075 to - I 4 mm - lon 

 and are probably present in all mammals in the cutis and the 



mucous membranes as the regular form of nerve-ending. The adventitia of the 

 double-contoured fiber passes over into the connective-tissue covering of the bulb, 

 the sheath of Schwann becomes thickened and it develops into the inner bulb, con- 

 sisting of cells of the longitudinal bulb. The spheroidal end-bulbs in man (nasal 

 mucous membrane, conjunctiva, mouth, epiglottis, folds of the rectal mucous 

 membrane) consist, according to Longworth and Waldeyer, in the interior of a 



FIG. 335. Longitudinal 

 End-bulb: a, the nu- 

 cleated sheath. 



