TORULA. 125 



contact. This parasite should be looked for on the under surface of 

 the youngest leaves, where the brown patch, with grey pellicle, forms 

 the characteristic feature of its presence. 



GENUS TORULA. 



The members of this genus come under the heading of the 

 " sprouting fungi," and have thus much in common, that their mode 

 of multiplication consists in a budding of daughter cells from the • 

 protoplasmic contents of the parent cell, and their separation and 

 free growth as individual plants. In their adult forms all consist of 

 rounded or oval cells, with a distinct limiting membrane and soft 

 protoplasmic contents. 



Torula cerevisle. — /// grape juice, appears in two forms. Low 

 yeast forms a fine amorphous deposit of a yellow grey colour in the 

 lower layers of the liquid. High yeast forms a layer of neutral tinted 

 matter close to the surface of the liquid, and this layer has more 

 coherence than is the case with the lower yeast. Each layer consists 

 of aggregations of oval cells; the lower layer being made up of separate 

 cells, the cells of the upper layer being in more intimate organic connec- 

 tion with one another. The cells are oval, and 8 to 9 ft. in length; 

 either separate, or in short branching chains. In some of the cells 

 are contained three or four spores, each 4 or 5 \j.. in diameter. 

 The plant will grow freely in saccharated solutions, or in Pasteur's fluid. 



Pink Torula. On Potato, &*c. — Grows as a rose-coloured succulent 

 film, if the soil be moist. On bread paste, if not very moist, it has 

 the appearance of pink coral (see Fig. 16, p. 59). 



In Gelatine. — It grows most freely at the surface, where it produces 

 its characteristic colour. It grows below the surface to a less extent, 

 following the line of the inoculating wire, and in this position it 

 assumes a grey tint, with a slight shade of pink in it (Fig. 39, p. 84). 



Microscopically. — It consists of rounded or slightly oval cells 5 

 to 8 jjl. in diameter ; and it is found that the pigment is here 

 present in the cells themselves, each of which has a delicate yellow 

 tint, so that when aggregated in large numbers the prevailing pink 

 colour is produced. J 



The spores of this organism are very widely disseminated, and are 

 so universally present in the air that it forms one of the most frequent 

 atmospheric contaminants of pure cultivation (Fig. 46, p. 89). 



Black Torula. On Potato, <&c. — Grows as a dull sooty crust, with 

 a dry, slightly furrowed surface. On bread paste it has a similar 

 appearance (see Fig. 30, p. 71). 



J?i Gelatine. — It grows chiefly at the surface as a black heaped-up 

 mass, and to a less extent in the track of the inoculating needle, 

 where it forms small black nodules. 



