462 H^EMOLYSINS AND ALLIED BODIES 



in many of the infections. Welch ( n ) suggests that some obscure 

 anaemias, not of infectious origin, may be associated with the 

 growth of certain haemolysin-producing saphrophytes in the tissues. 

 It is possible that anaemias produced by this cause might be 

 prevented by inj ecting anti-haemolysin ; in fact, Todd has shown 

 experimentally that a hsemoglobinuria produced in guinea-pigs by 

 injection of B. Megatherium can be prevented by the simultaneous 

 inoculation of an anti-serum. 



IV. H^MOLYSINS AND A&GLUTININS OF CERTAIN PLANTS 



These are called phytalbumoses, because they give chemical 

 reaction like albumoses ; ricin and abrin are the most important 

 members of this group. The former of these is obtained from 

 the seeds of the Ricinus Communis, from which also castor-oil is 

 prepared. It is very poisonous when inoculated into animals, 

 and its injection in gradually increasing sub-lethal doses leads to 

 the production in the injected animal of anti-ricin. Moreover, 

 this anti-ricin serum when inoculated into another animal (mouse) 

 will confer on it immunity against ricin inoculation. Kicin does 

 not possess any hsemolytic power, but it is capable of causing 

 agglutination of the erythrocytes of most animals, and an anti- 

 body to this reaction can also be produced by progressive 

 inoculation. The agglutinating and toxic actions seem to run 

 parallel with one another, and Jacoby ( 5 ) has recently shown that 

 a precipitate forms when a clear ricin solution is mixed with 

 anti-ricin serum. Jacoby describes the ricin receptor (that is, the 

 anti-body) as having three combining groups : one haptophoric, 

 uniting with erythrocytes ; one toxophoric, causing poisoning ; and 

 one agglutinophoric, causing agglutination. He was able to 

 produce three modifications of ricin, one in which the aggluti- 

 nating group remained active but the toxic one was saturated; 

 another in which the reverse obtained, and a third in which both 

 agglutinophoric and toxophoric groups were saturated. Perhaps 

 the most interesting part of Jacoby 's work, however, is that he 

 was able to prepare ricin free from any trace of proteid. All other 

 toxic substances which can produce antitoxins seem to be proteid 

 in nature, and the preparation of ricin in a proteid-free state 

 would tend to indicate that the apparent proteid nature of some 

 at least of the other bodies is due to admixture with proteid. It 

 should be mentioned here, however, that Osborne and Mendel ( 3G ) 



