SOME ASPECTS OF THE IMMUNITY QUESTION. 239 



although an exquisitely anaerobic germ, the bacillus maligni 

 cedematis grows excellently and maintains its virulence upon 

 agar or gelatine when the above-named micro-organisms 

 are associated with it (22). These results confirm in every 

 respect the earlier observations of Roger (23). That 

 rodents possess an immunity against the inoculation of 

 young cultures of tetanus bacilli or the spores has been 

 established by Vaillard and Vincent (24), who have shown 

 that neither the bacilli nor the spores develop when these 

 alone are introduced into the system. By using young 

 toxine-free bacilli, or by employing spores absolutely freed 

 from toxine, either by warming at 65° for twenty minutes, 

 or by repeated washing with water, it was found that, owing 

 to non-development within the organism, the effect of in- 

 jecting even 1 c.cm. of spore culture was inoperative, in other 

 words the tissues were exceedingly resistant to the microbes, 

 or, at any rate, offered an unfavourable soil. This inocula- 

 tion could, however, be rendered successful if a trace of lactic 

 acid or trimethylamin, or a non-pathogenic micro-organism, 

 such as bacillus prodigiosus, was simultaneously injected. 

 The natural tetanus inoculation accordingly cannot occur 

 without the association of other bacteria; these play the part 

 of the toxine, which is generally introduced with the patho- 

 genic bacilli, and this is decisive as to the results of injection. 

 This multiplication easily occurs in a suppurative wound, 

 where a local destruction of tissue is taking place. This 

 symbiotic life of the tetanus bacilli is, however, not supported 

 by other observers (25), but a renewed study of this question 

 enables Vaillard (26) to maintain his former position. Among 

 the recent literature dealing with Pfeiffer's influenza bacillus 

 it has been pointed out by Weichselbaum (27) that the organ- 

 ism attacked by influenza becomes exceedingly favourable 

 for the development of the diploococcus pneumonia;, and 

 even in typical uncomplicated cases this latter micro-organ- 

 ism is frequently observed. 



Defensive proteids or alexines have been isolated from 

 the spleen and lymphatic glands by Hankin, and from the 

 blood serum by Ogata, Tizzoni and Cattani, and it has been 

 believed that the immune condition may be related to the 



