Huber-DeWitt, Nerve-Endings in Muscles. 183 



of the motor nerve. Many of these nuclei are found in the thin 

 layer of sarcoplasma in which the axis cylinder branches 

 terminate. These nuclei are comparable to the so-called sole 

 nuclei, which, it will be remembered, were also regarded as 

 nuclei of the sarcoplasma — muscle nuclei. 



In our sections, we have recognized the nuclei described by 

 Kolliker, Ranvier and others, which form a part of what has 

 been regarded as the hypolemmal portion of the axis cylinder. 

 The nuclei in question are described by Kolliker as the nuclei 

 of the sheath of Schwann accompanying the ramifications of the 

 axis cylinder. That the terminal branches of the axis cylinder 

 are not invested with a continuation of the sheath of Schwann, 

 we have already tried to show ; such nuclei, if present, could 

 not, therefore, be regarded as nuclei of this sheath. In our 

 sections, nuclei are sometimes found very near one or the other 

 of the hypolemmal branches of the axis cylinder, as a, and a of 

 Fig. 12, may show. The differential staining used by us, and 

 the use of the micrometer screw of the microscope enable us 

 to state that such nuclei are not a part of the terminal branches, 

 but are always more or less distinctly separated from them. 

 Such nuclei have no doubt been interpreted as nuclei of the 

 hypolemmal branches in gold chloride preparations, where 

 such differentiation is not always possible. 



Before closing the discussion of the motor endings in am- 

 phibian muscle, attention needs to be drawn to a view ex- 

 pressed by Gerlach, namely, that the nerve fibers terminate in 

 an intramuscular network which pervades the entire muscular 

 substance, which network is in connection with the contractile 

 portion of the sarcolemma contents. That we may state Ger- 

 lach's opinion correctly, we give here his own words on the 

 subject : "Es existirt innerhalb des Sarcolemmas ein Axen- 

 fasernnetz, welches die contractile Substanz durchzieht, das in- 

 travaginale Nervennetz. Bei giinstiger Goldeinwirkung, 

 erscheint der ganze Muskelfaden von strichartigen Punkten 

 durchsetzt und zwar haben diese gesprenkelten Stellen ganz 

 dieselbe Farbe, wie die intravaginalen Nerven. Demnach muss 

 in dem contractilen Inhalt des Sarcolemmas eine Substanz 



