THE CYTOPLASMIC AND NUCLEAR CHANGES IN THE 

 STEIATED MUSCLE CELL OF NECTUEUS. 



BY 



ALBERT C. EYCLESHYMER, 



Professor of Anatomy, St. Louis University, St. Louis, Mo. 

 With 4 Plates. 



The striated muscle cell, although the subject of a voluminous litera- 

 ture, still presents many problems worthy of investigation. 



The unicellular character of the fibre has recently been questioned. 

 The method of increase in the number of cells, the mode of growth of 

 the individual cell, the origin of the sarcolemma are all problematic. 



The cytoplasmic changes deserve renewed attention. The presence of 

 fibrillae in the living cell is denied by many. Those who regard them as 

 veritable structures are not agreed as to their origin, their method of 

 multiplication, or their extent in the cell. The character of the cyto- 

 reticulum, the arrangement of its meshes, and the relation of the fibrillas 

 to these meshes, should be further studied. 



The nuclear changes especially merit extended investigation. The 

 method of nuclear division is undecided; nuclear movements have been 

 noted but not interpreted; nuclear structures, membrane, linin network, 

 plasmosomes and karyosomes undergo striking changes in volume, posi- 

 tion, and staining properties, but the significance of these changes is 

 unknown. 



The present study, while dealing to some extent with general prob- 

 lems in myogenesis, is devoted chiefiy to the cytoplasmic and nuclear 

 changes with the purpose of interpreting their relation during various 

 phases of cytomorphosis.' 



This work was begun in 1901 while the writer held an Austin Fellow- 

 ship in the Harvard Medical School. To Professor Minot the writer is 

 deeply indebted for guidance and encouragement. To Professor Barker, 



^ Minot, oi, 29, has used this word " to designate comprehensively all the 

 structural alterations which cells, or successive generations of cells, may 

 undergo from the earliest undifferentiated stage to their final destruction." 



Ameeican Jouknal of Anatomy. — Vol. III. 



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