296 NON-SACCHAROMYCETES OR DOUBTFUL YEASTS 



a well-developed scum, forming small islands, and an abundant de- 

 posit. The thermal death point is 65 C. in beer wort and water. 



Will's Torula No. 10. The cells of this species are similar to 

 those of No. 9. A powerful ring is formed, a well-developed scum 

 and a rich sediment. The thermal death point is about 60 C. 



Will's Torula No. 11. The cells are small, spherical and oval. A 

 ring is produced with a folded scum of a white color. At the end of 3 

 days, the surface of the culture fluid is covered with this scum and 

 at the bottom of the flask there is an abundant sediment. This 

 yeast succumbs at 65 C. in must and water. 



Will's Torula No. 12. This yeast is composed of elongated, or 

 fusiform cells closely resembling those of Mycoderma. There are also 

 present a few rounded and oval cells. A strong scum much folded 

 of a light yellow or brown color is produced. It may become a pale 

 red after three months. This scum resembles that of Mycoderma very 

 much. It appears soon as little floating islands which look like 

 fat globules. The thermal death point in beer wort and in water is 

 60 C. 



Will's Torula No. 15. The cells have different shapes, most 

 often elongated, oval or shaped like a sausage. The scum is well de- 

 veloped, very much folded and resembles that of Mycoderma. It has 

 a white, slightly yellow, color. It begins to appear at the end of three 

 days. The cells succumb at 65 C. in must and in water. 



Will's Torula No. 16. It is made up of spherical or oval cells 

 mixed with long cells. The scum is well developed, compact and of a 

 yellowish white color. A mediocre amount of sediment is formed. 

 The scum appears on the third day. The thermal death point in 

 must and water is 60 C. 



Will's Torula No. 17. The cells are small, quite round and pos- 

 sess the typical Torula shape. The scum is moderately developed, 

 compact and white. The thermal death point in must and water is 

 60 C. 



The greater number of these Torula are not distinct species. 

 More often they are of simple varieties or different races. All grow 

 at low temperatures on beer wort. The minimum temperature for 

 budding is 5-6 C. The optimum temperature is 30-35 C. Almost 

 all of them impart to beer wort an agreeable fruity odor. Species 

 Nos. 7 and 8, however, produce a disagreeable odor. 



Will 1 has recently described a number of other species found in 

 and about breweries. They have been characterized as follows: 



1 Will, H. Beitrage zur Kenntniss der Sprosspilze ohne Sporenbildung welche 

 in Brauereibetrieben und in deren Umgebung vorkommen. Cent. Bakt. Abt. 2, 

 46, 1916. 



