212 



The t'inl)rv() skin imd nil sai'coiiin cultivalod in the 

 plasma IVoni normal j^iiinea-pi^s, showed afler 18 hours 

 ineuhalioii a liixiii'iani growth in praclicall\' every prepara- 

 lion. '['lie i)rc])aralions eonlaining llie immune plasma were 

 on tlie eonli'ary much less aetive Ihouf^h the majority 

 showed, espeeially on Die third and I'ourlh day. a lair 

 out-wandering of eells. There was a definite difference in 

 the behaviour of both kinds of tissue in I he plasma from 

 the two animals treated. The tissues, skin and sarcoma. 

 both showed a more marked inhibition of ifrowth in llie 

 plasma from llie guinea-pii,' injected with sarcoma, than in 

 the plasma, from the guinea-i)ig injected with embryo skin. 



By injecting some guinea-pigs with a mucli larger dose 

 of rat sarcoma (0,65 gram) and some with a similar amount 

 of skin, the ])lasma had a marked increase of inhibiting 

 action of the tissues. The plasma from the animal previously 

 treated with a large quantity of embryo skin, was tlie most 

 toxic for both sarcoma and skin. A perfect disintegration 

 took place of the tissue explanted in this plasma. 



These experiments showed that there was no evidence 

 of even a relativelj^ specific action of the cytotoxins pro- 

 duced, the plasma from each animal having an equally 

 inhibiting effect on each kind of tissue. It was also ob- 

 served that defibrinaled rat blood could be used to im- 

 munize against both sarcoma and skin. Other experiments 

 showed that it was not possible to obtain specific cytotoxins 

 for either normal intestines or heart tissue of chicken. 



Similar experiments to L a m b e r t's have not been con- 

 tinued or taken up, since it is now possible to work with 

 pure strains of certain types of tissue cells. Possibly the 

 residts will be different from those already reported, because 

 earlier work was carried out with tissues containing all 

 kinds of tissue elements. 



i. Tumors. 

 Shortlj^ after Carrel and Burrows had improved 

 Harrisons technique of tissue explantation and extended 



