2/2 LECTURES ON IMMUNITY 



pectase, found in the juice of carrots, beets, etc. The co- 

 agulation is hindered by the presence of oxalate ions, i.e. 

 the presence of calcium ions (or ions of barium or stron- 

 tium) seems necessary also in this reaction. Acids retard 

 the coagulation, and strong mineral acids exert a greater 

 influence than weak vegetable acids. 



Coagulation or precipitation plays a very important 

 r61e in the chemistry of antibodies. We have already 

 spoken of the action of agglutinin as probably associated 

 with a coagulating influence upon the cells (cf. p. 164). 

 The agglutinating power of acids for erythrocytes is fol- 

 lowed by a very obvious coagulation. Corrosive sublimate 

 produces on erythrocytes^both coagulative and an agglu- 

 tinating action in higher concentrations, and a haemolytic 

 action in lower concentrations. Haemolysis and coagula- 

 tion (which makes itself manifest as agglutination) seem 

 to be so often concomitant in the so-called phytalbumoses 

 toxins of vegetable origin, as, e.g., ricin or crotin that 

 Ehrlich has assumed that they are in this case inseparable. 1 

 But for the bacteriolysins this is not the case, according to 

 Kraus and Ludwig. 2 



If toxins and antitoxins are mixed in higher concentra- 

 tions, they often yield a precipitate. Thus, for instance, 

 Jacoby 3 observed a flocculent precipitate on mixing ricin 

 and antiricin; and Hausmann 4 made a similar observation 

 for abrin and antiabrin. Bashf ord 6 found that blood-serum 



1 Ehrlich : " Schlussbetrachtungen " in " NothnagePs spezielle Pathologic 

 und Therapie," Bd. 8, p. 13, Vienna, 1901. 



2 Kraus and Ludwig: Witn. klin. Wochenschrift, No. 5 (1902). 

 8 Jacoby: Hofmeisters Beitrage, 1. 51 (1901). 

 4 Hausmann : Hofmeisters Beitr'dge, 2. 134 (1902). 

 6 Bashford : Journ. of Pathology, etc., 8. 59 (1902). 



