r.Ml] nil Phi/xirtil ('lioiiislri/ nnd llir DdctriiK' nf Tiiiiiiunili/. :> I '.) 



molecular weight of the agghitiuin in the bacilli is only two-thirds of 

 its molecular wci<fht in the surroundintr fluid. If the ai!:glutinin has 

 entered as a chemical compound in the bacilli, then the quantity of 

 agglutinin in each molecule of this compound is only two-thirds of 

 the quantity of agglutinin in each agglutinin-holding molecule in 

 the fluid. 



As is said above, after injection of red blood-corpuscles of one 

 animal into the veins of another animal, we find in the blood-serum 

 of the second animal a substance which hemolyses the red blood- 

 corpuscles of the first animal. This hemolysin loses its hemolytic 

 properties if it is heated for some time to 56° C. But it still contains a 

 substance, called immune-body, characterized by the fact that it gives 

 a hemolysin specific to red blood-corpuscles of the first animal if it is 

 mixed with some innocuous serum, e.g. serum from guinea-pigs. By 

 means of this property it is possible to determine the quantity of 

 immune-body contained in a certain volume of a fluid. The 

 aljsorption of immune-body in the red blood-corpuscles of the first 

 animal has been investigated l)y Morgenroth and myself. In this 

 respect it behaves exactly as the agglutinins. 



x\s instances the following measurements of Eisenberg and \o\k 

 regarding cholera-vibrions, and of Morgenroth and myself regarding 

 red blood-corpuscles from an ox may serve. The absorbed substances 

 were in the first case agglutinin against cholera vibrions, in the second 

 immune body contained in serum of a rabbit, treated with red l)lood- 

 corpuscles from an ox. T is the total (juantity of one of these sub- 

 stances in an arbitrary unit, B that part of it which remained in the 

 fluid, C the absorbed quantity. The following equations are used for 

 the calculations : — 



B -+- L 



L = KB-' 



The agreement between the observed and the calculated figures 

 may be regarded as quite satisfactory. The change of the values of 



