THE ADRENAL SYSTEM AND ANTITOXIC SERUM. 643 



conferring equal protection. Calmette, Phisalix, and Bertrand, 

 by treating animals as above, have obtained an antivenm which, 

 injected into vulnerable subjects, protects them, as do anti- 

 toxin, antiabiin, and an^ricin, against its own deleterious 

 effects. 



A feature common to all animals so treated, however, is 

 their tendency to "oversensitiveness" to the effects of the in- 

 jections, active and usually fatal symptoms of acute poison- 

 ing appearing suddenly in the midst of apparent health. If 

 this phenomenon is added to the adrenal signs already noted, 

 we are strikingly reminded of the critical stage of adrenal 

 overactivity and the sudden lapse of the glands into total in- 

 activity. The gradual habituation to the toxin, the vegetable 

 toxalbumin and the, venom, furnishes complementary evidence 

 as to the implication of the adrenal system in the process, typi- 

 fying as it does that observed in arsenic eaters and in such 

 conditions as morphinism, cocainism, etc. Indeed, it seems ob- 

 vious that the gradually increased injections do what all other 

 poisonous agencies do: i.e., they gradually increase and simul- 

 taneously develop the functional activity of the adrenal system. 



This peculiar oversensitiveness to the effects of toxins and 

 other interesting features of the problem that will assist in 

 elucidating the question in point are referred to by Joseph 

 McFarland, 26 as follows: "The occurrence of antitoxin in the 

 blood-serum is to be considered as a phenomenon of forced 

 immunization. During the immunization process it does not 

 seem to develop in proportion to the toxic endurance of the 

 animal, but, as Eoux has pointed out, is rather suddenly devel- 

 oped after the immunization has attained a high degree. Dur- 

 ing the continuance of the immunization it is a variable, not a 

 fixed quantity, and .while the toxin endurance of the animal 

 is kept up without variation, the antitoxin may gradually di- 

 minish. This I have seen many times illustrated in horses 

 producing diphtheria antitoxin, an excellent illustration being 

 afforded by one particular horse that furnished at one time a 

 serum containing 1400 units to each cubic centimeter of serum. 

 The immunity was maintained by cautious toxin injections for 



28 Joseph McFarland: "Text-book upon the Pathogenic Bacteria"; edition, 

 1900. 



41 



