Allen and Jolivette—Light Reactions of Pilobolus. 555 
and the culture from 2 t6 30 centimeters distant. Data for 
this series of experiments are given in Table IY. 
With the culture two centimeters from the opening, the total 
number of sporanges on the glass was 38. 15.8% were on 
area 1 and 39.4% on area 2, making 55.2% on the opening. 
18.4%were found on area 3, and 26.3% on area 4. 
At 10 centimeters from the opening, of the 198 sporanges 
fired in twenty-four hours, 51% were on area 1, 16.6% on 
area 2, 7.5% on area 3, and 24.7% on area 4. In this case 
67.6% were on the opening. 
At 20 centimeters distance, 98 sporanges were found on the 
glass. 32.6% reached area 1; 27.3% were on area 2. At 
this distance, then, 59.9% were on the opening, 14.2% were 
on area 3, and 25.5% on area 4. 
With the culture 30 centimeters distant, only 30 sporanges 
were fired. 30% of these were found on area 1 and 23.3% 
on area 2, making 53.3% on the opening. 30% were on area 
3, and 16.6% on area 4. 
The curve plotted from the percentages of the sporanges on 
the opening (Fig. 5 dash—dash line) and on areas 3 and 4 
Figs. 6 and 7, dash—dash lines) vary markedly from the cor¬ 
responding curves for the blue and white lights. The largest 
percentage found on the opening was 88.3% at eight centi¬ 
meters distance. From this point there was a decrease down to 
53% at 30 centimeters. At no point- was the percentage on 
the opening in the yellow light equal to that on the same area 
in the blue and white lights. 
In making these countings in the yellow light, the numbers 
of sporanges above and below the horizontal median line (A B, 
Fig. 3) were recorded. The majority of the sporanges are 
always found below the line A B. With the culture 12 centi¬ 
meters from the opening the number of sporanges below the 
line A B exceeds that above by 2%, at 24 centimeters by 10%, 
and at 30 centimeters by 26.7%. The number of sporanges 
above and below the line at the various distances are recorded 
fully in Table V. 
