Huber-DeWitt, Nerve-Endings in Muscles. 207 



the statements regarding these points made by Sherrington; we 

 may therefore give here his words : "I have seen spinal-gang- 

 lion fibers branch both when close outside and when quite 

 within the thickness of the capsule. The branching is usually 

 by dichotomous division at a node of Ranvier, and the angle 

 of divergence of the two branches is usually quite small. While 

 approaching the spindle the length of the sheath segments (in- 

 ternodes) of the spinal-ganglion fiber is from 600 ^ to 900 fx \ 

 at a variable distance within the spindle [We also find before 

 the spindle nerve pierces the capsule], the segments suddenly 

 become much shorter, 80 ;/ to 130 /^. At the same time, 

 dichotomous subdivision becomes much more frequent, the my- 

 elin sheath becomes much less thick, and the diameter of the 

 axis cylinder considerably greater, e. g. 14 j^i instead of 9 /^ ." 

 The ultimate ending of the spindle-nerves, i. e. the ending 

 of the non-medullated branches of the intrafusal portion of 

 the spindle-nerves, may best be described separately for 

 each of the classes of vertebrates studied. They have, how- 

 ever, this in common : the ultimate endings of the non-med- 

 ullated branches of the spindle-nerves are found outside of 

 the sarcolemma surrounding the intrafusal fibers, between this 

 sheath and the connective tissue sheath which, as above stated, 

 surrounds each intrafusal muscle fiber. 



On the ultimate ending of nefve fibers in muscle-spindles. 

 Amphibia. Our preparations were made from muscle-spindles 

 found in t\\Q cutanetis pectoris, port, sternalis anterior dir\d posterior 

 of m. pectoralis, and the sartorius. Especially in the first named 

 muscle, which so far as we may judge, contains from 4 to 5 

 muscle-spindles, the spindle-nerves may be readily stained in 

 methylene blue. Some of the preparations thus obtained were 

 fixed in ammonium picrate and mounted in glycerine-ammo- 

 nium picrate ; others were fixed in ammonium molybdate, em- 

 bedded in paraffin and sectioned. Dogiel has described and 

 sketched the ending of the spindle-nerves in the muscle-spin- 

 dles of the frog. A comparison of Fig. 8 of his article with 

 our Fig. 36, shows that we have corroborated his observations. 

 One, two, or even three large meduUated fibers are distributed 



