1899] IMMUNITY ACQUIRED BEFORE BIRTH 323 



difficult to deny the justness of the interpretation that in certain cases 

 there is a passage of antivirulent substance from the blood of a vaccin- 

 ally-imniune pregnant mother to the blood of the foetus, and that the 

 child may be in consequence born immune. 



The facts and arguments are briefly the following : — Immunity to 

 vaccinal inoculation was observed only in children whose mothers 

 were immune. Only in a small number of cases where the mother was 

 immune was the child immune. The intra -uterine transmission 

 occurred in cases where the maternal serum was antivirulent, 

 irrespective of the period when the mother was vaccinated. On the 

 other hand, the intra-uterine transmission was not observed in any 

 case where the maternal serum was non- antivirulent, although 

 vaccination had been effected shortly before or during pregnancy. 

 Therefore the condition of so-called congenital immunity is the trans- 

 mission of antivirulent substance from the maternal to the foetal 

 blood through the placenta. But the condition may be fulfilled 

 without result, for some of the newly born, whose serum was anti- 

 virulent, were still inoculated with success. In fact, the degree of 

 antivirulent potency is variable, but it may be said that the more 

 antivirulent the serum shows itself to be, the greater is the presumption 

 that the vaccinal inoculation will fail to have effect. 



Eel Poison and Cellular Immunity. 



The serum of eels is known to contain a " globulicidal " substance — 

 ichthyotoxin, of course — which destroys the red blood-corpuscles of 

 various animals into which it has been injected. The rabbit, for 

 instance, is peculiarly susceptible ; the red blood-corpuscles rapidly 

 lose their haemoglobin by diffusion when the eel-serum is injected, 

 even when it is diluted to xotloo" — ^wuo'U- 



Messrs. L. Camus and E. Gley, who have investigated the subject 

 {Comptes Eenclus Acad. Sci. Paris, cxxix. 1899, pp. 231-233), find that 

 the hedgehog is very immune, even against strong injections, and 

 experiments show that this immunity is due, not to the presence of 

 any " antiglobulicide " in the hedgehog's serum, but to the resistent 

 power of the red blood-corpuscles themselves. They have a natural 

 cellular immunity, wrongly called by the authors " immunite cyto- 

 logique." (If words mean anything it should be cellulairc, but the 

 mistake is a common one.) 



The frog and the toad, the hen and the pigeon, and Vespertilio 

 murijius, show the same cellular immunity. A peculiar fact is that 

 newly born, still blind rabbits, are similarly resistent, but the power 

 dwindles from the fifteenth day or so, and the adults have none. The 

 experimenters, in their interesting paper, cite the case of a doe-rabbit 



