889 



the result of concentric divisions; [le says p. 275: "C'est ainsi que 

 cette division pent efre concentrique et au lieu de donner naissance 

 a deux fibres acollées, pent séparer deux elements, I'un entonrant 

 I'autre comme les parois d'un tube entourent le mandrin qu'on y 

 introduit". 



It is a pity that neither in the text nor in the figures these 

 authors give any indication about the course of the fibrils, so that it 

 is impossible to compare their changes with those in our case. Their 

 interpretations appear to me to be not very plausible; it is difficult 

 to understand how it can be possible, that a new fibre develops 

 within the centre of an old one, and it is still more difficult to 

 imagine how a muscle fibre by means of division could give rise 

 to two concentric parts; both ideas are so little analogical with 

 other better known processes. 



Erb described in the dystrophia muscularis progressiva a second 

 peculiarity, which may be important in this respect; he saw in 

 transverse sections that many muscle fibres were encircled by very 

 small and larger muscle elements, which he could follow a good 

 way in the surrounding connective tissue; they seemed to bifurcate 

 there and resembled in their behaviour the capillaries. Erb considers 

 them fine bifurcations of muscle fibres and was reminded by them 

 of the so called ''Muskelknospen" of Neumann. 



Although these figures, superficially considered, have nothing to do 

 with ours, this statement of Erb seems to me of great interest. 



However important we must consider the above mentioned data 

 of the literature, still they do not explain to us the nature of the 

 changes in question. 



If we now try with the aid of the preparations to analyze the peculiar 

 figures, we must begin to look for the origin of the circular fibrils. 



In transverse sections we see that they are nearly always sepa- 

 rated from the central fibrils by a small fissure, but in longitudinal 

 sections we could demonstrate a distinct connection between them : 

 in some places we saw many central fibrils bend aside and join 

 the peripheral ones. Teased preparations taught us that the peripheral 

 fibrils do not follow exactly the circular direction, but often go 

 around the fibre in a spiral fashion. 



I should like to say thus, that the muscle-fibres give off here and 

 there thin lateral branches which do not enter into the surrounding 

 tissue, but remain within the sarcolemma and go around the fibre 

 in circles and spirals. 



The fibre is enveloped in this manner over a certain length by 

 a thick mantle of these branches, so that in cross sections we see 



