Allen and Jolivette—Light Reactions of Piloholus. 573 
7 To left of 1 ) 
13 On 1 > Left half of field. 
19 To right of 1) 
8 To left of 2 ) 
18 On 2 >■ Right half of field. 
3 To right of 2 ) 
68 Total 
The percentages (Table XI) that these number form of the 
total (68) are as follows: 
10.3 To left of 1 ) 
19.1 On 1 >• Left half of field. 
27.9 To right of 1) 
11.7 To left of 2 ) 
26.4 On 2 > Right half of field. 
4.4 To right of 2 j 
100.0 Total 
About 40% of the sporanges fired after the change in the 
source of illumination are in the right half of the field, clus¬ 
tered about, the new source. This 40% come from sporan- 
giophores which have completed a heliotropic reaction, al¬ 
though half of the crop of sporanges had been discharged at 
the time the new stimulus was presented. 28% are between 
the former opening and the middle of the field. This is a 
larger proportion than would have been found in this part 
of the field had there been no change in the direction of light. 
(Compare Table VIII, which shows 12% in this part of the 
field). It follows that the sporangiophores already aimed at 
1 began to swing over toward the new source of light and 
that the sporanges were discharged in some cases before the 
new heliotropic reaction had proceeded to its completion. 
A complete record of this series of experiments is given in 
Table X. Thom the records made in the evening (Part 2 
of Table X) the percentages found in the different areas in 
each experiment have been calculated (Table XI). Each 
horizontal row of figures represents one experiment, and in 
the column at the left is given the fraction of the total crop 
of sporanges which was found in the evening record. 
