178 LOCAL TLSSUE REACTIVITY 



colorations observed rapidly increased until in about six hours the 

 reactions became extremely pronounced, the areas being dark 

 blue in the central portion with deep red zones in the periphery. 

 A repetition of tlie toregoing intraperitoneal experiment, this 

 time using 12 rabbits and allowing only eighteen hours lor a 

 skin incubation period, gave positive residts in 6 rabbits. Another 

 repetition of the experiment allowing a skin incubation period 

 of twenty hours and using ■r] c.c. of the filtrate, j^er kilo of body 

 weight, gave a positive reaction in 1 out of (S rabbits so treated. 

 This aiuhor took adxantage of his observation in order to study 

 local j^eritoneal immunity. Rabbits in which the intraperitoneal 

 injection of B. lyjjho.su.s (ulture filtrate Avas able to elicit the 

 typical phenomenon in j)re\iously prepared skin sites ^vere ren- 

 dered negative to this ])hen()men()n by repeated injections of the 

 cidtme fiftrates intraperitoneal ly. It was then siiown that the skin 

 reactit^n coidd still l)e jjroduced if the reacting factors were intro- 

 duced intravenously. Frisch concluded that the immunity pro- 

 duced tmder these circimistances was of a distinctly local char- 

 acter involving only the peritoneimi and that the entire organism 

 was not yet immune. He fbiuid that betAveen three and four in- 

 jections of B. tyl)]iosi(s ctdture filtrates Avere necessary to render 

 the peritonetmi immune to this filtrate. The question of specificity 

 of this inmiunity was left open. It is possible that the preliminary 

 treatment of the peritoneum by repeated injections of the filtrate 

 called forth a non-specific response on the part of the cellular ele- 

 ments of the peritonetim which offer a histologic barrier to alj- 

 sorption of the reacting factors. This type of non-specific 

 imnumity was clearly demonstrated by the work of Gay (i92()) , 

 and Mallory and Marble (1925) , on mobilization of monocytes 

 in acute infections of serous cavities. 



I attempted to determine whether intracranial injections of 

 the provocative factors are capal)le of eliciting the phenomenon 

 of local skin reactivity. In preliminary experiments it was found 

 that when meningococcus "agar washings" filtrates were injected 

 intracerebrally, they consistently killed rabbits in dilutions as 

 high as 1:160 whilst the B. typhosus "agar washings" filtrates 

 seemed to be of lesser toxicity. The skin of rabbits was prepared 

 in the tisual manner with rrieningococcus or B. fypJiosus "agar 

 washings" filtrates and intracranial injections of the respective 

 filtrates were made tvventy-four, forty-eight, seventy-twc^, ninety- 

 six, and one hundred and twenty hours later. The fdtrates were 



