370 NORMAL HISTOLOGY AND ORGANOGRAPHY. 



peatedly, becomes non-medullated and finally ter- 

 minates in varicosities or expanded clavate ends. 

 The muscle spindle is a collection of delicate muscle 

 fibers enveloped in a dense perimysium sheath, the 

 whole being innervated by sensory nerve endings 

 much as in tendon spindles. The sensory endings 

 both in tendon and muscle transmit the sensation 

 of tension which becomes the basis for coordinate 

 movements. 



