Cl'LTURE MEDIA. 



The iiu'diiiiii lU'ccssary loi- llic ciillivalion ol' lissuc cells 

 oiilsidc Ihc body can be .sej)arale(l iiilo Iwo main compo- 

 nents, the s u J) J) o r I i n f^ a |) |) a r a I ii s o i- framework 

 and 111 e g r o \v I h-p r o m o I i n ii, s ii b s I a n e e s. 



Il has already been found by se\ci-al in\('sli<faloi\s Ihal 

 fragments of tissue transferred to a iicpiid medium die very 

 soon. 11 is therefore of vital importance that the cells find 

 some kind of solids to migrate on. if not. the cells Ijccome 

 spherical and succiunb progressively. Leo Loeb ''' has 

 the credit for being the first to study the influence of the 

 solid phase for the wandering of the tissue cells, and at the 

 same time, indicated the mechanism of the cell migration 

 in regard to the solids. Later 11 a r r i s o n -^^i) showed the 

 necessity of the framework in the culture medium for 

 the growth of nerve cells. E. riilenhuth ^■'\. P. Rons*^') 

 and myself ^^^) observed llie changes of the different cell 

 types into spherical forms, when the coagulated culture 

 medium became li(piid. It is consetpienlly necessiwy to 

 have some kind of support for the cells in the cultures. 

 When Harrison 247) studied the nerve regeneration in 

 vitro, he only found growth when using clotted frog lymph; 

 if il remained lifpiid no gi-owth took place. When Bur- 

 rows modified the lechnitpie by using blood plasma instead 

 of Harrison's lymph, the most ideal culture-medium for 

 tissue cells was found. Il is ideal because il is the most 

 natural condition for the cells and because it allows a 



