45 



in the examination of the matter. Thus 

 we come to the conclusion that the the 

 different antibodies are found tied to 

 different precipitinogens, some of which 

 can be easily differentiated and others in 

 which this difiereutiation is affected by 

 the fact that they cause a more or less 

 equal period on incubation in the rabbit 

 KRAUS and PRIBRAM even think on 

 account of the fact that some precipitins 

 remove from a certain quantity of deter- 

 mined sera one germ alone and need 

 very much more precipitating serum to 

 produce the same effect in agglutinins 

 of other animals of the same species, 

 that the same antibody may be tied to 

 different precipitinogens in the same ani- 

 mals (horse). This conclusions seem to 

 us to go to far and we believe that it is 

 really rather a case of a quantitative 

 ratio between the precipitinogen to which 

 the agglutinin is tied and the part of 

 this same precipitinogen without agglu- 

 tiniting groups which circulates certainly 

 side by side with it, and which is, 

 precipitated by the same kind of preci- 

 pitins. 



As seemed most strongly indicated, 

 we started the study of the relations of 

 precipitins to other antibodies (aggluti- 

 natins and antitoxins). 



A rabbit marked with picric acid, 

 was inoculated on: 



Jan. 21, 1920 with 10 cc. of an emul- 

 sion of B. mallei killed. 



Jan. 28, 1920 at 70o C. by two hours 

 exposure and simultaneously. 



Feb. 2, 1920 with 10 cc. of normal 

 horse servmi. 



Bled on Feb. 9, 1920 it gave precipi- 

 tating serum up to 1/10.000 and aggluti- 

 nins up to 1/1600. 



Technic : 



To 0,5 of rabbit serum were added 

 decreasing quantities of horse se- 

 rum at 1/10, 1/100, 1/1000, 1/10.000, 

 1/100.000. After two hours in the incuba- 

 tor at 37° C. and 24 hours in the refri- 

 gerator, the precipitates formed were 



removed by centrifugation and décan- 

 tation and the supernatant liquids v, ere di- 

 luted in such a way as to obtain serum 

 dilutions at 1/200, 1/400 etc. up to 

 1/6400, after having added to each tube 

 1 cc. of an emulsion of the germs. Con- 

 trol tubes treated in the same way had 

 the precipitinogenic horse serum subti- 

 tuted by physiologic saline solution. 



Reading was done after 24 hours m 

 the incubator at 37» C. In all the tubes, 

 even in the first, one, in which precipi- 

 tation was thy plentiful, the remaining li- 

 quid agglutinated the germs up to 1/1600 

 as in the control tubes. 



The conclusion to be drawn is that 

 the precipitins are not tied in the serum 

 to the fraction to which the agglutinins 

 belong and that the removal of this frac- 

 tion does not give the agglutinins either 

 greater affinity or greater activity for 

 the specific germs. 



With the antitoxins we were led to 

 a similar result: 



x\ horse was inoculated on: 



Sep. 17, 1919 with 100 cc. of tetanus 

 toxoids. 



Sep. 25, 1919 with 250 cc. of tetanus 

 toxoids. 



Oct. 6, 1919 with 250 cc. of tetanus 

 toxoids. 



Oct. 17, 1919 with 300 cc. of tetanus 

 toxoids. 



Oct. 29, 1919 with 400 cc. of tetanus 

 toxoids. 



Nov. 9, 1919 with 400 cc. of tetanus 

 toxoids. 



Nov. 19, 1919 with 450 cc. of tetanus 

 toxoids. 



Nov. 27, 1919 with 100 cc. of toxia 

 and formol (3 days contact). 



Dec. 10, 1919 with 150 cc. of toxin. 



Dec. 18, 1919 with 200 cc. of toxin. 



Dec. 19, 1919 with 500 cc. of normal 

 sheep serum. 



Dec. 30, 1919 with 250 cc. of toxin. 



Dec. 31, 1919 with 250 cc. of normal 

 sheep serum. 



