( 341 ) 



deviating growth on the iisiuil eiilture-media, shows very distinct 

 differences from the other pathogenic streptococci, whether from man 

 or from animals, tlie conchision is at liand, tiiat at least in the anti- 

 streptococcus serum, used by me, very little of the specific working 

 of the amboceptor is left. It is however quite possible that all patho- 

 genic streptococci, originating from man as well as from animals, 

 are very closely related, by which supposition one might keep at 

 least to the specific of the amboceptors. 



However later experiments have shown that the anti-streptococcus 

 serum is also active against micro-organisms, which do not belong to 

 the streptococci viz, pneumococci and meningococci. 



By the above is fully shown, that the specific action of the ambo- 

 ceptors in the serum of a horse to which large quantities of strepto- 

 cocci have been administered for a very long time, has strongly 

 decreased and made room for a more general action. Probably this 

 general working might be put to the account of one and the same 

 amboceptor, although the presence of more amboceptors in the same 

 cannot be denied. 



The above mentioned serum exercises, though in a small degree, 

 also a distinctly sensitive action on anthrax, typhoid and tubercle bacilli. 



From the above it appears, that the method of the combination 

 with the complement of Bordet — Gengou, is not to be used, if it is 

 necessary to distinguish nearly related bacteria from each other, which 

 in other ways are also difficult to separate. 



Granted that it must be accepted, that such a diminution of the 

 specific activity only takes place with sera of animals which have 

 been treated for a great length of time, so that the specific activity 

 of the amboceptor is more asserted in proportion to the shorter time 

 in which the animals are immunized, it is evident here, that there 

 is no question about a certain method being used, because one never 

 knows, — and this is also the case with sera of animals which have 

 only shortly been immunized — how far the specific action extends. 

 Even if it may be accepted that the horse, from whom the anti-strepto- 

 coccus serum originates, is a most favourable test-animal as regards 

 the forming of anti-bodies, then the above mentioned facts would 

 remain the same. 



DoPTER^) has recently found, that the amboceptor, present in the 

 serum of a horse which has been treated with dysenteria bacilli 

 (type Shiga) during 18 months, next to the action on these bacilli, 



1) Annales de I'lnst. Pasteur, T. 19. 1905, p. 753- 



