1914] JOLIVETTE—PILOBOLUS 97 
rangiophores. They were observed continuously, but there was no 
sign of a bending toward the light until 3:00 a.m. Meanwhile, 
the sporangial swelling had increased in size and the vesicular bulb 
was barely visible. At this time the sporangiophores were curved 
slightly at some distance below the sporangium nearer the direc- 
tion of the lamp. Observations were not made again until 4:30, 
when the sporangia were aimed directly toward the light and the 
vesicular bulb was distinct; the curvature was in the region imme- 
diately beneath the : 
vesicular bulb. -At 
6:30, when the ob- MI An [in Me a a 
servations were con- ea. ys 
cluded, the bulbs 
had swollen considerably. The sketches (fig. 11) show the develop- 
ment of one of the sporangiophores of the group. The development 
of all the others were remarkably parallel with the one described. 
Observations were begun using a second horizontal microscope 
on a sporangiophore at g:00 p.M., November 2, tg11. ‘The tip of 
the sporangiophore was just beginning to swell. The sporangium 
was standing vertical to the surface of the substratum. The light 
was placed at the angle above mentioned. The development of the 
sporangial swelling continued, but no reaction toward the light was 
visible at 11:35. Observations were made con- 
tinually until 3:00 A.M., when the sporangium 
was rather well formed and the vesicular bulb 
barely visible. 
; On the evening of November 3, 1911, two 
Fic. 11 sporangia were observed for the first time at 
10:40. The first sporangiophore was yellow 
and rather blunt tipped, but as yet it did not show sporangial 
swelling. It stood at an angle of about 20° from the vertical, thus 
being inclined away from the light at an angle of go°. There was 
no sign of a response toward the light at 12:00 P.m., but the tip 
then showed the sporangial swelling. At 2:05 A.M. the sporangio- 
phore began to curve toward the light, the region of curvature being 
then located at some distance below the sporangial swelling. At 
2:15 the curvature was more pronounced but still confined to the 
