Ward. — Some Thames Bacteria. 295 
ones form discs, with the Ascococcus-like groups im- 
bedded. 
On the third day they are like irregular milky drops, too 
thick to show structure. 
Stab-cultures at 12-15 0 form a wet, glistening, thin 
white frond above and yellowish-white, dense, dot-colonies 
in the tunnel. In a week the frond has nearly covered the 
surface of the gelatine, and is depressed in the middle, 
slightly sinking into the gelatine ; while the colonies along 
the tunnel enlarge and tend to radiate into the surrounding 
gelatine. The sinking goes on until the frond lines the sides 
of a distinct funnel, devoid of liquid however ; and the sub- 
merged colonies form cloudy outgrowths and widen the tunnel. 
The sinking and softening of the gelatine continue, and are 
very decided in a fortnight to three weeks (Fig. 8). 
At 20° C. the phenomena are similar but quicker. In five 
days the softening of the gelatine is pronounced, the sub- 
merged colonies confluent ; and a good funnel with signs of 
liquefaction and running are evident in ten days. The growth 
is equally good — or even a little better — in slightly acid 
gelatine, as compared with slightly alkaline. 
The growth is easily removed by the needle, but does not 
lift as a whole membrane, and is firm and waxy or slightly 
slimy. Even after ten weeks there is no real liquefaction 
of the gelatine, but the cloudy white growth was penetrated 
far in. 
At 20° in sugar-gelatine, a milk-like spreading drop formed 
above, and a considerable confluence and growth in the tunnel 
in three days. 
Streak-cultures at 20° show a dull, translucent, white growth, 
yellowish if held down, bluish by transmitted light, thin at 
the margins, spreading slowly, and softening the gelatine in 
eight or nine days, and beginning to sink along the axis 
( F >g- 9 )- 
In a month a deep spoon-shaped scooping has occurred, 
in which the cloudy white growth floats in viscid softened 
gelatine. 
X 2 
