TISSUES OF THE BODY. 



321 



owing to the difficulty of investigation, whether this took place externally 

 on the sarkolemma, or after perforating the latter in the interior of the 

 fleshy substance. 



Fig. 309. Distribution of nerves in a voluntary muscle from the frog. a. a nerve 

 fibre destitute of neurilemma, showing repeated subdivision down to apparent!} 

 terminal filaments 6, b; c, an undivided nerve fibre with a thick envelope. 



From a whole series of recent investigations, among which those alone 

 of Beale, Kuhne, Margo, Koellilter, Krausc, Rouget, Engelmann (3;. need 

 here be mentioned, the conclusion has been arrived at that this early 

 view is likewise untenable, and that the true ending of the fibres takes 

 place far beyond these apparently terminal twigs. 



But in what form and where this final cessation of the fibre is situated, 

 whether within or external to the sarkolemma, is a point about which 

 considerable difference of opinion still prevails. 



Beale, Krause, and Koelliker believe the fibre to terminate externally, 

 while the other observers are of the opinion that it perforates the sarko- 

 lemma ; and we believe rightly. 



In fact, we may see, on examination of the muscular fibres of verle- 



