158 



HISTOLOGY 



fibril has become separate from the others; frequently it shows varicose 

 enlargements. 



Free sensory endings occur not only in stratified epithelia, but also in 



Medullated Muscle 

 nerves. fibers. 



Medullated nerve fiber. 



Terminal ramification. Tendon bundle. 



FIG. 149. TENDON SPINDLE OF AN ADULT CAT. X 80. 





t jL ^ ^ 



~ Medullated nerve fiber. 



~f; 



~^~~" Axis cylinder. 

 ~ Nucleus of a tendon cell. 



FIG. 150. THE LEFT PORTION OF FIG. 149. X 345. 



muscle, tendon and connective tissue. In simple epi- 

 thelia the free endings may be sensory, but in glandular 

 epithelia they are often efferent fibers, inciting the cells 

 to glandular activity. The ultimate branches of the 

 nerves are so delicate that they cannot be seen in 

 ordinary preparations; they have been demonstrated 

 chiefly by the methylene blue method, applied to very 

 fresh or living tissue. 



In the epidermis, as a modification of the free end- 

 ADULTCAT.XI35- j n g Sj fib ers are found terminating in disc-shaped net- 

 works (tactile menisci) at the base of modified cells (Fig. 147). These 

 tactile cells may occasionally be seen in ordinary preparations. 



FIG. 148. MUSCLE 

 SPINDLE OF AN 



