NOTE ON A PINK TORULA. 247 
temperature of the room, it was noticed, after some days, that the 
growth appeared on the surface of the nourishing material in the 
shape of minute whitish spots or flat droplets, which, as they 
gradually enlarged, assumed a distinct pinkish colour. The enlarge- 
ment in breadth and thickness proceeded in a few days so far that 
the whole surface of the almost solid nourishing material became 
covered with a pinkish film, in which, however, the individuality of 
the droplets could still be recognised. Under the microscope these 
pink droplets are composed entirely of torula cells of exactly the 
same nature and size as those above described. They are, no 
doubt, the same organisms, as will appear also from other facts 
presently to be mentioned. 
The cells themselves do not possess any colour when looked at 
under the microscope, singly or in a thin layer, but they appear of 
a pinkish tint when viewed as a group, or in a thick layer. 
I have sown out from this layer of pink torula cells on to boiled 
white of egg, solid gelatine, and mixture of gelatine and pork 
broth, used in my experiments on Anthrax bacillus. With the egg 
I have not obtained any satisfactory results, but with the gelatine 
and the mixture of gelatine and pork broth, I have obtained 
beautiful crops. The sowing was done with the point of a capillary 
glass tube on to the free surface of the nutritive material (contained 
in flasks or test-tubes, plugged with sterilised cotton wool) ; and 
after an incubation of about four days, the vessel being kept at 
ordinary temperature of the room, there appeared the first signs of 
the growth having taken root, in the shape of a minute pinkish 
droplet; this gradually spread in breadth and thickness. ‘The very 
interesting fact observed with this increase was this: the masses 
growing downward into the nutritive material remained colourless, 
whereas those spreading on the free surface were pink, both being 
composed of exactly the same torula cells. 
The thicker the layer became, the deeper the pink tint. The 
gelatine does not become liquified by the growth, and in this 
respect it differs from a growth of micrococci, bacteria, or bacilli. 
Sowing the pink torula into the depth of fluid nutritive material, 
such as pork broth, and keeping it at the bottom of the fluid, it is 
noticed that no matter whether growing at ordinary temperature of 
the room, or in the incubator at 30—35° C., it remains colourless, 
and when of considerable amount, appears like a whitish precipitate 
at the bottom of the fluid. 
Sowing this colourless torula on to a free surface, it again gives 
origin to pink growth. But also in the same tube the at first 
colourless torula, z.e. while growing at the bottom of the fluid, may, 
when reaching the free surface, give origin to the pink growth. 
Another interesting fact I have observed is this, that when a 
copious growth of pink torula has made its appearance on the sur- 
