238 



S 111 y I li likfwist' tcslcd llic nclion ol' (li|)hl('ri;i loxin on 

 llu- tissue <»i"()\vlh ill xiiro I'lic l('cliiii(|ii(' he iipplit'd in 

 1!>1 I IT) \\;is |)i-()l);il)ly not llic \ cry l)csl lie concluded 

 Ilia! ciiickcn |)lasnia has a marked haclericidal action on 

 till' l)ac. typhi, which may. in some sii<*hl decree. i)e over- 

 come liy the presence of ,i<r{>\\in<» tissue, especially' splecnic 

 tissiu- in the cultures. 



On hac. dyscnteriie the bacterici(hd action of cnicken 

 plasma is present, but niucli less niarkedh% and the same 

 antagonistic action ol tlie tissue was observed. 



Chicken |)lasiiia has little or no bactericidal action on 

 bac. cob. 



On bac diphteria' chicken plasma is strongly bactericidal 

 and the action is counteracted by the presence ol' the tissue 

 in til'.' culture. 



Smyth '^-' observed also the interesting fact, that many 

 bacteria' stimulated tlie jirobferalion of tissue cells. This 

 1 can fully confirm through occasional obserxalions. 



Mosl interesting are the observations of S m y t h '"^^ on 

 the action of tnliercle bacilli on various tissue cells grown 

 in vitro. I'lie gi'owtli of the fibroblasts and ejiilhelial ele- 

 ments, llie formation of the epitheloid cells and giant cells, 

 the degeneration and disintegi'ation of the tissue cells was 

 beautifully observed. 



.3. Specificity of the tissue ceils. Cijtotoxins. 

 For the demonstration and the study of the specificity 

 of cytoloxins. the tissue culture technique is a method which 

 will admit of the dii-ect oliservation of cells in an undis- 

 turbed state for a definite i)erio(l of time. The tissue culture 

 technique was primarily used for this particular study 

 l\v Lambert and llanes wlio i)erceived llie importance 

 of this investigation. The application of this technique is 

 dependent ui)on the jiossibility of cultivating in vitro the 

 various cells in ])ui-e strains. Since 1911. when Lambert 

 and llanes look up this study, tlie techiiicpie of cultivating 



