IMMUNOLOGICAL RELATIONSHIPS 34I 



I. Seventeen normal male rabbits. II. Seventeen normal female 

 rabbits. III. Eleven rabbits showing strongly positive reactions. 

 The bacterial filtrates nsed for elicitation of the phenomenon 

 were "agar Avashings" filtrates meningococcus 44B., B. typJiosus 

 and B. coU. Studies Avere made on bleedings one to two hours 

 before the preparatory injection and four and t^venty-four hours 

 after the provocative injection. IV. Nineteen rabbits failing to 

 develop reactions. The filtrates used in these rabbits were "agar 

 ^vashings" filtrates of meningococcus 44B., meningococcus 44D., 

 B. typlwsus, B. coli and Streptococcus viridans. The determina- 

 tions were timed as in Group III. V. Six rabbits receiving intra- 

 venous injection alone of "agar washings" filtrates of meningo- 

 coccus 44B. and 44D. and B. typhosus. Determinations were made 

 on bleedings one to two hours before the intravenous injection 

 and four and twenty-fom- hours after the intravenous injection. 

 \T Ten rabbits recei\ing intradermal injections alone of "agar 

 washings" filtrates of meningococcus 44B. and 44D., and B. ty- 

 pJiosus. The determinations were made before and twenty-four 

 hours after the intradermal injections. VII. Nine rabbits received 

 one sensitizing intravenous injection of horse serum. Six days 

 later meningococcus "agar ^vashings" filtrate Avas injected intra- 

 dermally and twenty-foiu' hoins later horse serum Avas injected 

 intravenously. Eight of these rabbits sho^ved strong local reac- 

 tions following the intravenous injection of horse serum. Three 

 rabbits Avere treated in the same manner except no preparatory 

 injection of bacterial filtrate ^vas made. In all these rabbits the 

 determinations Avere made before the first intravenous injection 

 of horse serum; six days after the intravenous injection of horse 

 serum; and foiu" and twenty-four hours after the second intrave- 

 nous injection; and then again six days after the second intra- 

 venous injection. The doses of bacterial filtrates injected intra- 

 venously were variable and ranged from one to several hundred 

 reacting units. 



The results of the investigations of Mintz were as follows: 

 /. Bleeding Time. (Method: Sticking of marginal vein of rabbit's 

 ear, blotting the drop gently Avitii filter paper every one-half min- 

 ute.) Averages of differences between successive determinations 

 in all categories showed nothing significant. The average bleed- 

 ing time was two to two and one-half minutes. In a few individual 

 instances there was a reversal of the bleeding time going from a 

 diminisiicd to a slightly increased time or vice versa. This could 



