OBSERVATIONS ON THE HISTOLOGY OF STRIPED MUSCLE. G7 



" sarcoplasma." Each muscle-column consists of alternating 

 thick and thin segments ; in the centre of each thin segment is 

 a dark granule. The thick segments of the muscle-columns 

 correspond to '^ Bowman's sarcous elements," and the dark 

 granules in the centre of the thin segments correspond to 

 '' Krause's membrane " or the '^ transverse network" (fig. 13 

 and diagram B). 



Diagram A (high focus). Diagram B (low focus). 



The sarcoplasma is the part which is stained in gold prepara- 

 tions. In short, Rollett regards the appearance of gold 

 preparations as due to the staining of the sarcoplasma, and 

 considers this to be a honeycomb of interfibrillar material, and 

 not a true intra-cellular network. 



The latter portion of Rollett^s paper is devoted to an 

 elaborate criticism of the network view of the structure held 

 by Melland, Van Gehuchten, Carnoy, and myself. He states 

 that what we describe as the fibrils of the network are only 

 transverse and longitudinal sections of the walls of the honey- 

 comb or sarcoplasma (" Was beide Autoren an diesen als Faden 

 beschreiben sind uur Quer- oder Liingsschnitte der Wande des 

 Wabenwerkes, welches das Sarcoplasma um die Muskelsaulcheu 

 bildet," p. 252). 



He describes the appearances seen in fresh muscle-fibre as 

 follows : — At low focus (diagram B) the muscle-columns appear 

 dark and in a line with the granules, the sarcoplasma appearing 

 light. At high focus (diagram A) the sarcoplasma appears dark, 

 the muscle-columns light, and two rows of granules appear in a 

 line with the sarcoplasma and alternating with the muscle- 

 columns. He states that the dark lines drawn by Melland 



