130 



PERIPHERAL NERVE TERMINATIONS 



the skin. Ruffini * states that they occur in large numbers in the 



skin of the finger tips, where they rival in number the rather more 



deeply placed Pacinian corpuscles. 



/^ ^> x The Ruffini organs are cylindrical 



in shape and their nerve fibres usually 

 enter at the side of the organ, though 

 occasionally at its end. Now and then 

 a single branching nerve fibre is dis- 

 tributed to several of these end 

 organs. 



III. END BULBS (Krause). These 

 structures, together with those which 

 follow, form the so-called encapsulated 

 nerve end organs. In the end bulbs 

 the nerve forms a terminal arboriza- 

 tion of varicose and knobbed fibrils 

 which freely anastomose (Dogiel, Ruf- 

 fini). The bulb is invested with a 

 distinct connective 

 tissue capsule. On 

 entering the bulb 

 the nerve fibre 

 loses its sheaths 

 and the perineu- 

 rium becomes con- 

 tinuous with the 

 capsule of the 

 bulb. Within the 

 capsule the nerve 



fibrils are embedded in a granular inner bulb. 

 The end bulbs vary much in both size and 



shape. They may be either spheroidal, ovoid, 



twisted or convoluted, branched or compound, 



or cylindroid. They are abundantly found in 



the conjunctiva, but also occur in the corium 



, . o'-i 1-111 The nerve fibre shows 



of the skin. Similar, though more highly de- lateral processes, many 

 veloped, end bulbs form the so-called genital of which are knobbed. 

 corpuscles which are found in considerable 



r 



FIG. 128. A PACINIAN CORPUSCLE 



FROM THE PLEURA OF A CHILD. 



a, lamellae ; 6, nerve fibre ; c, 

 nerve. Methylen blue. Moder- 

 ately magnified. (After Dogiel.) 



FIG. 129. PACINIAN COR- 

 PUSCLE FROM THE 

 MESENTERY OF A 

 KITTEN. 



numbers in the connective tissue of the glans saia.) 



Methyien biu& Motor- 



ately magnified. (After 



* Arch. ital. de biol., 1894. 



