2 Journal of Comparative Neurology and PsycJiology. 



Primitivfibrille, oft wohl bereits Elementarfibrille, an einer bestimmten 

 Stelle meiner Praparate zu verfolgen im Stande bin." ' 



In 1877 Gerlach described the nerve endings of the frog 

 as branching dichotomously to form an intravaginal network 

 which runs through the contractile substance of the muscle fiber 

 in close relation to, if not in actual continuity with, the con- 

 tractile fibrillae. He appears to have been influenced in his 

 deductions by the fact that in staining with gold chloride, he 

 obtained reactions from certain elements of the sarcous sub- 

 stance which were similar to those obtained in nerve endings. 

 In 1889 he repeated these investigations with methylene blue, 

 and claimed that this method substantiated his previous views. 

 Subsequent research by others has not confirmed his results 

 nor upheld his deductions ; nor can his own drawings be said 

 to support the claims he attempted to establish. To one con- 

 versant with intra-vitani staining with methylene blue, it will 

 appear a very doubtful procedure to base results on the simi- 

 larity of staining reactions. By this intra-vitam method one 

 constantly sees fine blue-stained fibers in the intermuscular con- 

 nective tissue which, taken alone, might simulate nerve fibrillae. 

 At times one observes beautifully stained examples of myo- 

 fibrillae either as very fine closely-arranged points or as continu- 

 ous structures. On this ground alone, therefore, it is obvious 

 that it would not be possible to deduce a nervous plexus either 

 within or without the muscle-cell. In addition, there must 

 be present an undoubted continuity of structure with an unmis- 

 takable nerve fiber, together with any characteristic appearance 

 which one is accustomed to find in corresponding terminals. 



In 1896 Apathy drew attention to the manner in which 

 the axis cylinder divides in invertebrate muscle fibers. He de- 

 scribes the primitive fiber as entering the muscle cell and there 

 dividing into fine fibrillae (primary fibrils). These, however, 

 do not form a plexus but either send comparatively thick 

 branches (secondary fibrils) to adjacent muscle-cells there to 

 form terminations from which it may be that further branches 



> Mitheil. a. d. Zoolog. Station zu Neapel., Bd. XII, 1S96, p. 505. 



