71 



Peripneumonia.— Peripneumonia » of cattle is the only filterable 

 virus which has so far given a visible growth on artificial media. 

 Collodion sacs were filled with Martin's peptone bouillon, to which 

 was added a little serum of the rabbit or cow in the proportion of 1 : 20. 

 The' sac was then inoculated with peripneumonia and placed in the 

 peritoneal cavity of rabbits and cows for fifteen to twenty days. 

 The fluid became turbid and in it, under a magnification of 2,000 

 diameters, could be seen the most extremely small, moving, strongly 

 refractile points. In a series of subcultures made from such a growth 

 the last of the series was virulent. 



The colonies on agar mixed with bouillon-serum, were transpar- 

 ent, small, and made up of exceedingly fine particles whose form it 

 was impossible to determine. The microbe of this disease was made 

 to pass the Berkefeld and Chamberland F filters, but when an 

 albuminous diluting liquid was used, it could not be made to pass 

 either. 6 



Foot-and-mouth disease.— Loeffler and Frosch ° state that lymph 

 was taken from the blebs of calves suffering with this affection, 

 diluted with 35 parts of water, and then passed through a filter 

 candle. The filtrate, in amounts which correspond to one-tenth to 

 one-fortieth cubic centimeter of the original lymph, when injected 

 into calves caused them to sicken in two days, the same as the con- 

 trol animals into which were injected equal amounts of unfiltered 

 fluid. 



McFadyean says that foot-and-mouth disease passes the Berkefeld 

 filter when in watery suspension, but is arrested when in an albumi- 

 nous fluid. 



Nocard d says that aphthous fever passes through Berkefield, Cham- 

 berland, and Kitasato filters. 



South African horse sickness. — Nocard a succeeded in passing the 

 virus of this disease through a Berkefeld filter only. 



McFadyean e reports that pure blood taken from an animal sick 

 with the disease was passed through the Berkefeld filter under a 

 pressure of 26 inches of mercury and the filtrate, when inoculated 

 into a horse, produced the disease. 



When the blood serum was diluted with four parts of water and 



« Nocard, Roux, Borrel, Salimbeni et Dujardin-Beaumetz : Le microbe de la 

 peripneumonie. Ann. de l'lnst. Pasteur, vol. 12, 1898, p. 240, etc. 



6 Nocard, Roux, and Dujardin-Beaumetz : Etudes sur la peripneumonie. Re- 

 cuil de med. vet, 1899, 8e. ser'ie, Oct. 26, 1899, p. 441. 



cLoeffler and Frosch : Bericht der kommission zur erforschung der maul 

 und klauenseucUe bei dem Inst. f. Infek.-krank. in Berlin. Centbl. f. bakt. 

 u. infek., 1898, bd. 23. 



* Nocard : La " horse sickness " ou " maladie des chevaux de l'Afrique du 

 Sud. Bull, de le soc. centr. de med. vet., n. s., vol. 19, 1901, p. 37. 



« Journ. cornp. path, and therap., 1900, XIII. 



