260 SUMMARY OF CURRENT RESEARCHES RELATING TO 



vapours of the original phosphorus, affect the nutrient properties or the 

 reaction of the media employed. For hanging drop cultures, special 

 cells were devised to protect the media from the vapours of phosphorus 

 and from its oxides. Test tube cultures were made by substituting 

 a few small pieces of phosphorus for the pyrogallic acid of a Buchner's 

 apparatus. On addition of the potassium hydroxide solution, phosphoric 

 pentoxide is formed, which at once takes up water to form phosphoric 

 acid, which descends as a white cloud ; in a few hours the main portion 

 of the oxygen is absorbed, but complete absorption does not result until 

 after 24 hours at the temperature of the incubator. 



Spores of B. tetani, in 1 p.c. glucose broth, germinated overnight 

 at 37* 5° C, and went into spore-formation in 48 hours ; stab cultures 

 of this organism grew equally well at the surface and in the depth of the 

 stab ; growth was more rapid than by Buchner's method. 



Asp>ergiUus niger, a strict aerobe, refused to grow ; Penicillium 

 glaucum also refused to grow, and still showed no growth on subsequent 

 exposure to air, the spores being destroyed by the absence of oxygen. 



B. pyocyaneus and B. megatherium, facultative anaerobes, showed no 

 growth within 24hours ; B. coli communis and B. typhosus at 37*5° C, 

 in glucose broth, showed abundant growth within 24 hours, the colonies 

 of B. coli being thin and transparent, those of B. typhosus being denser. 



Details are given for modifying the method when applied to plate 

 cultures, or for numbers of tube cultures and Smith's fermentation tubes. 



In glucose gelatin stabs B. graveolus, B. pyocyaneus, B. megatherium, 

 B. anthracis, Staphylococcus pyogenes aureus, Sarcina lutea, and Proteus 

 vulgaris grew feebly, and produced neither liquefaction nor pigment, 

 but on being exposed to the air they regained their vigour and properties 

 of liquefying and producing pigment. The inversion of cane-sugar 

 bouillon inoculated with yeast and also with a mixed culture of inverting 

 forms, was prevented by keeping the cultures in anaerobic conditions. 

 The oxygen was so completely absorbed by the phosphorus that un- 

 inoculated media, stained with litmus or methylen-blue, were decolorised 

 within 24 hours. 



Cultivation of the Amoebae of Tropical Dysentery.* — A. Lesage 

 succeeded in cultivating amoeba? from intestinal mucus in the following 

 way : Mucus was taken from, say, 10 places and transferred to as many 

 Petri's capsules. Only capsules which contained living amoeba? were 

 retained, the others being rejected. The living amoeba? were then culti- 

 vated in fiat glass vials or in test tubes, the medium being agar, which 

 had been washed for 8 days and afterwards sterilised. 



The cultivation temperature was from 18° to 25°. The essential 

 feature of the method was to prevent the amoeba? being overgrown by 

 bacteria. 



In a few days, small amoeba? could be found. Cultivations were also 

 made on plates on which a paracolon bacillus was growing. In this way 

 living amoeba? could be passed from the human intestine on to a plate 

 without going through the encysted stage. 



Another method consisted in cultivating amoeba? from the encysted 

 forms. Some mucus containing living amoeba? was placed in a glass 



• Ann. Inst. Pasteur, xviii. (1905) pp. 9-16 (2 pis.). 



