30 



obsci'vod in a ril)i"in-rrc'e medium Ihal llic most'iichymc \wo- 

 (liK'c's riiic c-()iili';iclilc libi'ils alter Iweiily-rour h(nirs ol' 

 cullivaliori ami by staining lor milochondria these c(nil{l be 

 found present in Ilic line fibrils. 



Concerning llu- cartilage '", there seem to be interesting 

 processes to sludy in regard lo the inlercelluhir siibslaiice, 

 which seems lo disa|)])i'ar when the cartilage is ciillivaled 

 embedded in the |)lasma clol and the cells fall a])arl and 

 resemble a cullure of yeasi, but cultivated on the free surface 

 of the plasma clol, the cells spread out, grow as do epithe- 

 lial cells, adhering in solid membranes. II can now be 

 considered as a fact Ihat cartilage, as well as epithelium 

 can be brought lo live outside the organism for any length 

 of lime. 



Another question which has caused an endless and life- 

 long discussion viz: whether the invading cells under condi- 

 tions of inflammation are derived from Marchand's leuco- 

 zytoid cells or from Maxim of f's polyblasis, seems intlie 

 culture work to stand an opportunity of being .solved, v. 

 Recklinghausen showed thai the pus cells and while 

 blood cells were the same thing and C o h n h e i m observed 

 Ihat the while cells wandered out from the vessels under 

 conditions of inflammation. His ingenious experiments on 

 the excised cornea will be remembered. 



It is well known what an incessant and life-long sti'uggle 

 P. Grawitz23o) h^d because of his statement that pus 

 cells are derived from the fixed tissue cells when their 

 respective supporting substance is destroyed. Doubtless 

 his statements are nol absurd. Leo Loeb's ^'^^) experiments 

 on the regeneration of epithelium show that the infiltration 

 could be explained that way. In recent investigations on 

 growing cartilage in vitro i^*), we have an example which 

 shows how the intercellular substance can be brought to 

 disappeai- under certain conditions. The changes of any tis- 

 sue cell into the spherical shape can be seen any day in 

 the tissue cultures. The studies of the origin of the diffe- 



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