250 LOCAL ILSSUE REACTIVITY 



mice could he obtained (oiisistently by intravenous and intra- 

 peritoneal injections. The subcutaneous^ injections j)roduced 

 hemorrhages ol simihu' severity. A ie^v ol)ser\ati()ns seem to sug- 

 gest that the incidence ol regressions of ttnnors may be lo\ver in 

 mice tluis treated. 



Meningococc tis "agar washings" fdtrates injected intra\enously 

 in doses ranging from 750 to '^000 reacting imits killed 2G out of 

 29 tumoi -bearing mice \\ithin twenty-loiu" hours. Intraperitoneal 

 injections of the liltrates in doses of 1000 and 2000 reacting units 

 killed 9 of the 1^; timior-bearing mice within twenty-fom^ hours. 

 From twt^ to tvventy days later, 6 more mice from the above 

 groups died. Thus, only one out cjf the 42 tumor-l^earing mice 

 sur\i\ed the intravenous and intraperitoneal injections. 



The lethal effect of meningococcus filtrates on normal mice was 

 considerably lower. Of 37 mice injected intravenously and in- 

 traperitoneal ly with meningococcus filtrates in doses of approxi- 

 mately similar range, only 19 mice died. Here again the highest 

 mortality rate vvas observed within the first twenty-four hours. 



Comparison of toxicity of intravenous and intraperitoneal 

 injections brought out a curious fact. The intravenous and in- 

 trajDcritoneal injections were of ecpial toxicity to tiunor-bearing 

 mice. Thus, all of 13 tmnor-bearing mice injected intraperito- 

 neally and 28 out of 29 tiniior-bearing mice injected intrave- 

 nously were killed. The intravenous injections, h.owever, ap- 

 peared to be decidedly less toxic to normal mice than the 

 intraperitoneal injections. Thus, death occurred in 9 out of 23 

 normal mice injected intravenously with doses ranging from 1500 

 to 3000 reacting iniits and in 9 out of 1 1 normal mice injected 

 intraperitoneally with the same doses. 



Subcutaneous injections of meningococcus "agar washings" fil- 

 trates in dosage ranging from 750 to 3000 reacting units were 

 less toxic than intraperitoneal and intravenous injections to 

 tumor-bearing mice. In this series, 7 out of 32 tumor-hearing 

 mice survived. As was shown, similar doses injected intravenously 

 and intraperitoneally killed 41 of 42 tumor-bearing mice. There 

 was a certain irregularity in the lethal effect of subcutaneous 

 injections of the filtrates upon tumor-bearing mice. Thus, the 

 subcutaneous injection of 3000 reacting units killed 5 mice 



'^ The subcutaneous injections were always given at a disiaiue not less than i 

 inch (2.5 cm.) from the srte of the tinnor. 



