Huber-DeWitt, Nerve-Endings in Muscles. 219 



stained in methylene blue and alum carmine or cochineal, where 

 they are in the immediate vicinity of vessels, or in a vessel wall. 

 This may be seen in Fig. 34, s. n. 



In closing this account, we may briefly refer to the probable 

 function of these muscle-spindles. What we may have to say 

 on this point has been implied in the preceding pages in discus- 

 sing the endings of the spindle-nerves. Our observations have 

 been entirely histological. That the muscle-spindle is a sensorial 

 end-organ, situated in voluntary muscular tissue, there seems 

 to us to be no doubt. The general structure of the spindle- 

 organs, their rich nerve supply, and the distinctive ending of 

 the spindle-nerves, would alone, it seems to us, warrant such a 

 conclusion ; this seems to us fully substantiated in Sherrington's 

 observations showing that the spindle-nerves are spinal root 

 ganglion nerves. 



It has been suggested by Kerschner and Sihler, no doubt 

 on a priori grounds, that the spindle-organs may have to do 

 with the muscle sense. Sherrington has shown that under a 

 large aponeurosis, belonging to the distal portion of the vastus 

 medialis, spindle-organs are numerous. He states: " If this 

 aponeurosis be thoroughly separated, however carefully, I have 

 always found the' ' knee-jerk ' irrevocably lost from the 

 muscle." 



A study of the structure of the spindle-organs (we refer 

 here more particularly to their capsule, peri-axial lymph space, 

 etc.) and their resemblance in these respects to other sensorial 

 end-organs — Pacinian and Herbst corpuscles — causes us to 

 agree with Sherrington when he states : "That the stimulus to 

 which these organs are especially adapted is mechanical in 

 quahty." 



