202 SPECIAL BACTERIOLOGY 



trace of pleuro-pneumonic serosity in sacs of collodion, which were 

 carefully sealed and inserted into the peritoneal cavity of rabbits. 

 After fifteen to twenty days, the sacs contain an opal, slightly turbid, 

 albuminous fluid, but neither contain cells or bacteria cultivable in 

 ordinary bouillons. 



Microscopical Examination of the contents of the sacs with a very 

 high power (about 2000 diameters) revealed infinite, small, refringent, 

 mobile points of such a degree of fineness that it is impossible even 

 after coloration to exactly determine their form. A second sac con- 

 taining the identical bouillon, minus the pleuro-pneumonic serosity, was 

 inserted into the peritoneal cavity of the same rabbit, in order to 

 ascertain if the modifications found in the fluid of the first sac were not 

 due purely and simply to the osmotic changes which take place in the 

 vicinity of its walls. The liquid contained in this sac was found to have 

 retained its transparency and primitive limpidity. The numerous 

 mobile points that, despite their extreme fineness, had rendered the 

 inoculated liquid opalescent, were in reality living organisms which had 

 exhibited infinite growth, in consequence of the modification undergone 

 by the culture liquid, and thanks to the obstruction by the collodion to 

 the phagocytary action. This is proved when two sacs of inseminated 

 collodion are inserted into the peritoneum of a second rabbit the first 

 with a trace of the opal liquid thus obtained, the second with several 

 drops of the liquid previously heated, and consequently containing no 

 organisms, comports itself like the sac receiving no serosity, and its 

 contents remain limpid and transparent, whereas the other soon 

 becomes opalescent and contains the innumerable refringent points 

 described above. 



Fresh sacs were inseminated with the opal liquid obtained from the 

 fertile sac of the second rabbit, and inserted into the peritoneum of the 

 third rabbit, and so on, successively identical results being always ob- 

 tained. It is advisable to use several sacs in each passage, as they are 

 frequently ruptured. The rabbits frequently become very thin previous 

 to being destroyed, and sometimes succumb before the time set for the 

 autopsy, when they are found in a profound state of cachexia, being 

 nothing more than skin and bone. No appreciable organic lesions are 

 discovered at the autopsy ; the blood and pulp of the parenchymatous 

 organs sown in various media, also in collodion sacs, does not give rise to 

 any cultures, so that it seems in all probability to be an intoxication due 

 to diffusion outwards of the products elaborated by the microbe in the 

 collodion sacs. 



It cannot be attributed in every case to digestive or other troubles 

 which might be caused by the sac and foreign body, because several sacs 

 of bouillon containing no serosity can be inserted into rabbits, and 

 conserved there for several months, without the animals showing the 



