ENCAPSULATED SENSORY FINDINGS. 



105 



way that the nerves ramify (Fig. 125). These cylinders lack the distinct 



capsules which characterize the nerve corpuscles. 

 Terminal corpuscles are nerve endings consisting of a coarse nerve 



fiber or knot of small branches surrounded by a semifluid intercellular 



substance (which is granular in preserved tissue) and enclosed in a con- 

 nective tissue capsule. The terminal 

 ramifications of the nerve show irregular 

 swellings or varicosiiies, such as are found 

 along terminal nerve fibers generally and 

 which are not considered artificial. Some 

 authorities describe the interlacing termi- 

 nal branches as ending blindly, but others 

 believe that they unite so as to make a 

 network. Often more than one fiber en- 

 ters a corpuscle and it has been suggested 

 that they include afferent and efferent 

 fibers. Generally the connective tissue 

 sheaths of the entering fibers blend with 

 the capsule of the corpuscle, and the mye- 

 lin sheaths are lost just inside the capsule. 

 Terminal corpuscles have been grouped 

 as tactile, genital, bulbous, articular, (cylin- 

 drical), and lamellar. 



il 



FIG. 125. TERMINAL CYLINDER. 



(After Ruffini, from Ferguson's 



Histology. 

 gH, Medullary sheath; il, terminal 



ramifications of the axis cylinder ; 



L, connective tissue. 



FIG. 126. TACTILE CORPUSCLE FROM A PERPENDICULAR 

 SECTION OP THE GREAT TOE OF A MAN TWENTY- 

 FIVE YEARS OLD. X 560. 



n, Medulla ted nerve fibers; e, varicosities; h, connective 

 tissue sheath. The nuclei are invisible. 



Tactile corpuscles [of Meissner] are elliptical structures, 40-100 // 

 long and 30-60 fi broad (Fig. 126). They are characterized by transverse 

 markings due to the corresponding elongation of their capsule cells and 

 nuclei. From one to five medullated fibers enter the lower end of a tactile 

 corpuscle, losing their sheaths on entering. Some fibers may pass straight 



