ON THE DEVELOPMENT OF THE CONNECTIVE TISSUES 

 FEOM THE CONNECTIVE-TISSUE SYNCYTIUM. 



FRANKLIN P. MALL. 

 From the Anatomical Laboratory of Johns Hopkins University. 



With 18 Text Figures. 



It is much disputed whether the connective-tissue fibrils arise within 

 cells or from a substance between them. It matters little which view 

 is entertained, the evidence in either case is unsatisfactory. The many 

 researches upon the development of the connective tissues have not 

 given results fully satisfactory and the reason for this is only too 

 evident to those who have made this subject a special study. To be 

 sure material is very abundant and at first sight the problem is a simple 

 one to be solved easily. 



The first marked step in advance regarding the histogenesis of con- 

 nective-tissue fibrils was made by Flemming in 1891/ to be followed 

 by a second communication in 1897.^ According to Flemming, the 

 fibrils of white fibrous tissue are formed in the protoplasm at the 

 periphery of the cell, then gradually thrown off, after which they may 

 still continue to grow. Simple as this is, it is extremely difficult to 

 prove; for with this problem many others are associated to cause 

 complications. 



While there are a number of investigators who support the view of 

 Flemming, there are also a number who oppose it. One of the most 

 recent is Merkel,' whose studies were upon the human umbilical cord. 

 Merkel comes to the conclusion that the white fibers are formed in the 

 intercellular substance, as taught by Kolliker. It is unnecessary to 

 enter more into the literature of this subject, for it would only result 

 in arranging the authorities into one group or another, or into an indefi- 

 nite group. The literature has been collected recently in the article 



1 Flemming:, Virchow's Festschrift, Berlin, 1891. 



2 Flemming, Archiv fiir Anatomic, 1897. 



3 Merkel, Verhandl. d. Anatom. Gesellscliaft, 189.5. 



