2i8 Journal of Comparative Neurology. 



may be gathered from their brief descriptions, it may resemble 

 the endings found in the rabbit. 



Sherrington asks the following question: "Is the intrafusal 

 muscle, like the rest of the muscle, connected directly with 

 motor nerves ? " In attempting to answer this question with 

 the gold chloride method, he states that he was unable to find 

 motorial end-plates on the intrafusal fibers. He found, however, 

 that by degenerating all the nerves going to a muscle (cutting 

 the sciatic nerve of a cat under the gluteus muscle), the striated 

 muscle-fibers of the gastrocnemius and intrinsic plantar muscles 

 were completely degenerated, while the intrafusal muscle-fibers 

 were not altered from their normal. He further states : " The 

 intrafusal fibers seem in regard to their nutrition to be largely 

 independent of both the afferent and the efferent nerves of the 

 muscle, if one may judge by absence of obvious degeneration 

 in them for five months after total enervation." On the other 

 hand, Kerschner finds, as' previously quoted, that the intrafusal 

 fibers possess a motorial ending. He states : "Der motorische 

 Nervenfaden (oder mehrere solcher) welcher gesondert oder mit 

 den sensiblen Fasern eintritt, lauft eine Strecke weit mit dem 

 Muskelbiindel parallel und endet in ziemlicher Entfernung vom 

 sensiblen Endapparate mit kleinen motorischen Endgeweihen." 

 In a number of instances, we were able to find what we have 

 interpreted as motorial endings on the intrafusal fibers ; /«. e. in 

 Fig. 37 and 39, show such endings. More often, have we found 

 meduUated nerve fibers, smaller than the spindle-nerves, accom- 

 panying them to the spindle, but usually they could not be 

 traced to the endings. These may have been motor fibers. We 

 are inclined therefore to agree with Kerschner, that some of the 

 intrafusal fibers at least have a motorial ending. The ones we 

 have found, were, so far as we now remember, always distal to 

 the sensory ending — the ending of the spindle-nerve. 



We may further mention that we have, now and then, in 

 rare cases, found sympathetic nerve-fibers in the capsule of the 

 muscle-spindles. These are shown in Figs. 38 and 39, s. n. 

 They are, no doubt, vaso-motor fibers of the spindle vessels, as 

 such fibers are now and then seen in muscle-spindles double 



