MYCODERMA LEBENIS 337 



ordinary yeasts but usually smaller. The cells are rarely united one 

 to the other and are only grouped two by two. This yeast is a strong 

 oxidizer. It oxidizes sugar to carbon dioxide and water. When in- 

 troduced into a flask of sugar media which are easily aerated, the al- 

 coholic fermentation is set up, but not as much sugar is transformed as 

 by ordinary yeasts. It does not form more than 3 per cent alcohol. 



MYCODERMA FROM PINEAPPLE. Kayser l 



This yeast, isolated from pineapples, has elongated or elliptical 

 cells (3.5-7 X 2.5-5 /x). Sometimes the cells are spherical, remaining 

 attached in chains of 4 or 5 cells each. After 24 hours, in all car- 

 bohydrate media slight acid with a scum and ring is produced. The 

 cells formed are like those formed in the deposit. In all media in 

 which they grow, a pleasant ether odor is produced. The thermal 

 death point in the moist state is around 53-55 C. and in the dry state 

 100-105 C. At these temperatures, the cells are killed in 5 minutes. 

 Kayser has also isolated many mycoderma yeasts from bananas. 



MYCODERMA LEBENIS. Rist and Khoury 2 



This species was isolated from leben. It has cells about 68 JJL long 

 and 3/x wide, either isolated or forming groups in mycelium. In this 

 latter case, the units are long and thin (33 /z long and 1.5 to 2 JJL thick). 

 The ends are enlarged, giving somewhat the appearance of bis- 

 cuits. The lateral buds give rise to secondary chains at almost right 

 angles. The protoplasm is finely granular with large fat globules. 



On the surface of plain gelatin, the colonies are grayish white, 

 opaque and a little raised, with a circular edge later indented with 

 stratification in concentric zones. On carbohydrate gelatin, the 

 colonies are exclusively aerobic and of a greenish gray color. The 

 center is surrounded by an arborescent structure. Stabs in lactose 

 gelatin develop abundantly on the surface but slowly in the depths. 

 The culture resembles an inverted cone. On the surface of gelatin, a 

 thin crust, dry, nacreous, much firmer in the periphery than in the 

 center, is formed. No liquefaction of the gelatin is accomplished. In 

 milk bouillon, the Mycoderma grows badly and forms a thin scum, 

 transparent and gray, which is attached to the walls of the culture 

 flask. The liquid becomes cloudy and there is a deposit in the 

 bottom of the flask. There is no fermentation of lactose. On grape 

 must, there is produced an active fermentation and a thick scum. 



1 Kayser, E. Note sur les ferments de 1'ananas. Ann. Past. Inst. 5, 1891. 



2 Rist, E., and Khoury, J. Etudes sur un lait fermente comestible, le "leben" 

 d'Egypte. Ann. Past. Inst. 16, 1902. 



