23 
to cells, adapted to 64 M.C. at different times after the beginning 
of the darkening. See Table II and Fig. 2 curves 1, 2,3,4,5. The 
first = 15 min. after the darkening 256 M.C.S. has no effect on 
RE T 5 ef 
DONKER-ADAPTATIE EN LICHT-GROEIREAGCTIE. 
DONKER 
164MK DONKER 
64MK | DONKER 
64MK] DONKER 
64MK | DONKER 
‚64MK [DONKER | 
0 10 20 30 40 50 60 MIN. 
Fig. 2. Dark-adaptation and light-growth response. 
the growth (curve 1), whereas this quantity does cause a maximal 
response by dark-adaptation (curve 6). 
TABLE II. Response to 256 M.C.S. of cells, adapted to 64 M.C., at 
different points of time after darkening. 
ui | S39 2u Maximum Minimum 2nd max. 
OBE) ES20 | in pere. 
a a 5 ee a after min of the after in perc after in 
Dis | ME aS ‘| growth | PG perc. 
N m.eon in dark | 
| . 
20 min. | 6%—8% |8 —10 m.| 107% | 13Ye— 1512 96 | — os 
25 min. | 54-7 [6 — Th, 132 1221412 83 19 —21% | 105 
30 min. | 4 -6 |6%— 8 5 144 122 — 1542 74 | 21Ve—24e | 116 
40 min. | 4 —6 [6 — Th, 160 12/s—15 69!/ 20 —23 | 1124, 
2 hours | 4 —5'2 (6Ve— 8, 176 14 —16 8312 | — = 
(full 
adap- 
tation) | | 
Table Il and fig. 2 clearly show the increasing adaptation in 
