TABLE OF CONTEXTS. 
Page. 
Maternal transmission of immunity to diphtheria toxine 1 7 
The employment of “used” guinea pigs as breeders 7 
Summary of literature on heredity in immunity 8, 9, 10 
Tables showing results of tests of young guinea pigs bred from “used” 
mothers 11, 12 
Table showing that some horses fail to produce any antitoxin or only small 
amounts 13 
The effect of repeated injections in the mother on her young 14 
Immunity not transmitted to second generation 16 
The cumulative effect of diphtheria toxine 17 
Maternal transmission of immunity to diphtheria toxine and hypersusceptibil- 
ity to horse serum in the same animal 18 
Experiments 18 
Results 19 
( 5 ) 
