102 BOTANICAL GAZETTE : [FEBRUARY 
failed to strike the openings were found in the strips adjacent to the 
openings and only a very small percentage fell outside this area. 
It is plain from these data that although there is much varia- 
tion in the number of sporangia fired toward the two openings, the 
sporangia cluster about each of the openings and show no tendency 
to strike between the two. The sporangia are discharged, there- 
TABLE I 
‘ 
‘ fe 
eo 
a 2 35 
“a a a a: 
i) 8. a 3 
B =) io) 
86 I 1] gl29| 6 I 11/25] 3 --| = 
60 3) 54-4031 si20] 18) x | 12 Bae Meee 
590 4 ieee a 3 3| rolrS | rol 2{ r{ri...| 3 
56 ed ae ees .| 2 a st Seta Oe) 2 aft 
25 Cee in ae tee pray Ceerd Gent 9 ae sa iy at oe ee a a ee 
41 219] 4! 2 hs ae iS (a Se oe Bee ob de ere Oa 
22 : Ce RE HIS a EF Py ea 
35 ee a eg or a OR eT Ales | | 8 
as ee 5/13 Ee ee eek be ead EE REE els -| 9 
36 Sie a Ae hgh stat et 2 | x .| TO 
54 Ore ty Stet 2 Pick al at Gas wg 4 2 Ir 
29 I 1. Sts Ij 2 Clb a 7 Ree Gee eae 12 
24 2) 4 a} :2 : a ee eee ae 13 
24 Il 9 3 r| & I 14 
14 Ij 4 5 ek Theecte 15 
24 a ey a ee x} x} 3] ¢ sae 16 
a0 as 3 re Pat eae 31 7 
12 4 eek ree ey a 1}. I ene 18 
20 I EL, ot pal ee a 7 eats 19 
7 2 2 12 een a Uae Oe 4 
35 t)--3\20.| 8) 2 RE BE Pte os [es fe 
27 2;8) 2) 4 2| 3 Pot 22 
14 5 I is aa Pees 23 
22 114 Dee aoe oe ye ies. Bale 24 
34 6/12 eet ck a becals “eae 2 ae 25 
142 e}55.| 4) 20134 | 27) 2) 2 hy r0ig0) 6) 2 |. 20 
204 2131] 4! 231390! of 613 I tl 7| 20158 | 20| 4 |. 27 
334 |- r|x}21| 3] 24184| 2315] 4]2]6] 3] 9} 34/78] 30) 8} 2/313 | 28 
133 I 2) 8 a GE Sas Be 2 3} 6} 16/32 Pe ay oes Bee 29 
178 |. Ete ts 8} 26/52 | 28} 6 | 1] 2412 1| 2| 16jaz GS tee ee 1 | 3° 
146 I A aaiae Sta a a |. ft 3 4) azi4g | 7|-<:| 3 |---].2 | 3% 
24 I 2 ie Gs Os tn ee ae FN es ee Ca Wd I Bian 
252 1|/2/3|2{/31] 5] 25a5| 16)8|51]41]5]| 5] 12] 22144] 3319] 91| 8 | 6 | 33 
61 2 2 2 Stato) I wits | 4) 371 2 | 2 )---| 34 
30 |. [2 ee I 2 pron Para we aia ae 4.2) 41.2 GE ficctescte+s} So 
176 |. x|21]5]| 17} 15] 9] 6)...| 3 |...| 8 | 23].25| 20lz9 | 13| 5 | 8 | 4 | 3 | 3° 
fore, toward one or the other of the two lights. In other words, as 
shown by the earlier set of experiments, there is no resultant 
reaction due to the presence of the two lights. If there were, the 
sporangia would be for the most part between the two openings. 
It is clear, therefore, that this simple organism, when subjected 
simultaneously to two equal light stimuli, will respond to one of 
the two stimuli, to the complete exclusion of the other. 
