CONCENTRATION OF ANTIBODIES 141 



in i : 20 ; the pericardial and cerebrospinal fluids and the aqueous 

 humor, however, gave no reaction in i : 10. 



Of the five attempts to produce precipitins in dogs by immuniza- 

 tion with horse serum, four were entirely negative, and even in the one 

 positive result only the serum, thoracic lymph, and the neck lymph 

 contained precipitin. The precipitation occurred in a higher dilution 

 in the thoracic lymph than in the serum, but only in the lower dilu- 

 tions of the neck lymph, which was considerably weaker than the 

 serum. 



Our data are not uniform enough nor extensive enough to warrant 

 us in drawing conclusions. It is apparent that dogs develop pre- 

 cipitins with extreme difficulty, and that a good method of immuniza- 

 tion is by single, large, intraperitoneal injections. The results that 

 we have seem to show that the precipitins follow closely the hemag- 

 glutinins and the hemolysins in their distribution in the various body 

 fluids of immune animals, altho we have not as yet been able to 

 demonstrate any in the pericardial fluid. 



BACTERIAL AGGLUTININS. 



We also made a study of the concentration of the agglutinins for 

 the typhoid bacillus in the various body fluids of normal and immu- 

 nized cats and dogs, and intend later to extend the work to cover 

 the bacteriolysins. 



Nuttall,34 employing both the hanging drop method and the plate method, found 

 bacteriolysins for the anthrax bacillus in the aqueous humor and the pleuritic exudate 

 of dogs and rabbits. Prudden38 found bacteriolysins in the amniotic, hydrocele, and 

 acites fluids. Meltzer and Norris 28 found the thoracic lymph nearly as bacteriolytic as 

 the serum for the typhoid bacillus. Widal43 found agglutinins for the typhoid bacillus 

 active in a dilution of i : 60 in the pericardial fluid, while the serum of the same patient 

 was active at 1:350. Edema fluid was found strongly agglutinating also, but the 

 result with cerebrospinal fluid was negative. Picks? found that cerebrospinal fluid 

 agglutinated at a dilution of i : i and i : 2. Kohler 20 found agglutinins in the cerebro- 

 spinal fluid in one case in ten examined of non-typhoid patients, and but three times 

 out of 19 cases of typhoid fever, and these in dilutions of i : i, 1:5, and i : 10. Braude 

 and Carlson? made a study of the concentration of the agglutinins for the typhoid 

 bacillus in the body fluids of normal and immunized cats and dogs. Inasmuch as they 

 used for comparison the action of the fluids of the same animal upon the same bacterial 

 suspension, their results give more nearly the true conditions of the body fluids in an 

 animal; they avoided the error which a comparison of the body fluids of different 

 animals is sure to introduce on account of the wide individual variations. The hanging 

 drop method which they employed, however, is not considered as accurate as the pre- 



