568 MICROBIOLOGY OF THE DISEASES OF MAN AND ANIMALS. 



lungs or by rubbing them into the skin. It is probable that the highest 

 concentration of agglutinins results from the injection of dead bacteria. 

 It is, however, necessary that these bacteria be not subjected to a tempera- 

 ture above 62. A large majority of pathogenic and non-pathogenic 

 bacteria form agglutinins when injected into the body. Obviously, the 

 concentration of these agglutinins differs greatly. Very high agglutinat- 

 ing sera are noted, such as, for example, one in one million when B. 

 typhosus is used and one in two million when Msp. comma of Asiatic 

 cholera is used. Often two strains of the same organism will vary greatly 

 in their power to produce agglutinins. Again, the concentration of the 

 agglutinins in an infected animal varies from day to day, and in order to 

 make an accurate observation, it is necessary to make repeated exami- 

 nations on subsequent days. For example, in typhoid fever the agglu- 

 tinins one day may be thirty times as strong as on a subsequent day. 



The Distribution of Agglutinins in the Blood. As before stated these 

 antibodies are found in practically all the body fluids. They reach their 

 highest concentration in all probability in the blood serum. In certain 

 cases they are in high concentration in the milk. Agglutinins are also 

 present at times in the sputum, tears, and the humors of the eye. 



Inherited Agglutinins. Agglutinating substances may be transferred 

 from the mother to the offspring in utero. It has been frequently demon- 

 strated for example, that the offspring of mothers who have recently re- 

 covered from typhoid fever or are infected at the time of birth, have agglu- 

 tinins in the body fluids. The same is true of the offspring of glandered 

 horses. Notwithstanding the fact that the milk is frequently rich in 

 agglutinins, these substances are not transferred to any great extent by 

 this means to the offspring. 



The Substances Concerned in Agglutination. There are two distinct 

 substances concerned in this reaction. One substance which is present 

 in the serum or body fluid of the infected or immune individual and other 

 substances which are present in the microorganisms which are agglutin- 

 ated. The substance in the serum, as before stated, is known as the 

 agglutinin, the substance (antigen) in the bacteria or other microorganisms 

 is known as the agglutinogen. When agglutinin and agglutinogen are 

 combined together a new substance is formed which is designated as an 

 agglutinate. As to the location within the bacterial cell of this agglutin- 

 ogen there is some dispute. Various authorities have stated that it is 

 present in the cell wall or on the cell wall. Others have held the view 



