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Anthropoden. Biol. Centralbl. 11, No. 24. 



Nachdruck verboten. 



The Relation of the intercalated Discs to the so-called 

 "Segmentation" and "Fragmentation" of Heart Muscle. 



By H. E. Jordan, Ph.D. 

 Professor of Histology and Embryology, university of Virginia, 



and 



James Bardin, M. D. 



Formerly Pathologist to the Central State Hospital, Petersburg, Va. 



With 7 Figures. 



In view of a number of observations recently made by one of 

 us (Jordan) ujjon the histology of heart muscle, we believe that a 

 review of the question of the anatomical basis of "segmentation" 

 and "fragmentation'' of the heart will be of interest. Since it was 

 first reported by Renaut and Landouzy in 1877, the histology, and 

 the pathological significance, of rupture of cardiac fibres have received 

 wide-spread attention, and an extensive literature upon the subject 

 has come into existence. 



Practically all the opinions in respect of ''segmentation" and 

 "fragmentation" put forward in the literature up to the present time 

 have been founded on the assumptions that cardiac muscle possesses 

 a cellular and not a syncytial structure, and that the various patho- 

 logical findings in "segmented'' and "fragmented'' hearts are to be 

 interpreted as conditions affecting respectively intercellular and intra- 

 cellular portions of the heart tissue. The observations recently made 

 by us upon ruptured heart muscle, and interpreted from the point 

 of view of Jordan's theory of the nature of the intercalated discs, 

 to a great extent fail to agree with the histological data put forward 

 by earlier students, and make necessary a new interpretation of "seg- 

 mentation" and "fragmentation''. 



