211 



thai il is a ti-anst'onnalion of llic lihrin-ncl \n llu- plasma 

 clol When tin- ciilliircs <rcl older, llic cnlirc i)lasma is 

 Iransroniu'd lo thick, reticular and branching librilkv. 



Scrum i)rci)aralions always Failed lo show any fibre for- 

 mation, which indicates that the fibres are lormed by a 

 transformation of the fibrin-nel and not as an oulgrowlh of 

 the embedded tissue. My own experimcnls on the cullivalion 

 of comjjlex tissues in serum seem lo confirm Ibis. 



If tissue juice is added to Ihe })lasma. but no tissues, 

 no fibres are formed. In other experiments B a i t s e 1 1 ad- 

 ded to the plasma dead blood cells and in other experiments 

 living blood cells or starch grains. In the plasma, lo which 

 living blood cells were added fibres were formed ~ but 

 not in the plasma containing the dead cells or the starch 

 grains. Hail sell found that a mere manipulation of the 

 plasma with the preparation needles caused the formation 

 of fibrillse. This indicates that mechanical factors play an 

 important role in the formation of fibrillar. 



In these studies of the transformation of the clot in 

 tissue cultures, living tissues were present and allhrough 

 these experiments indicate that the formation of the fibres 

 was not due to an intracellular action, the question could 

 possible be solved by the elimination of the living tis- 

 sues from the plasma. B a i t s e 1 1 shows therefore in a 

 very striking way that the plasma clot can be transformed 

 to a new fibrous tissue, without the presence of any tissues, 

 but under the influence of various mechanical factors. 



A typical clol of plasma, as it can be obsci'\Td 

 with the ullramicroscope, is a netw'ork of connecting fila- 

 ments, a crystalline gel. The coagulation as it is observed 

 through the ullramicroscope, is beautifully described by 

 Baits ell and accompanied walh photographs. By pressing 

 the coverglass against the fibrin clot during the coagulation 

 for a short time, big consolidated fibrillse are formed which 

 look exactly like these found in vivo. If the fibrin clot 

 is exposed to a pull, one will see fibrillse in the direction 



