22 
Newcombe, Sensitive Life of Asparagus plumosus. 
tken rose to 20° below yertical for 2 days — then declined to 
45° and experiment ended. Total hight of sboot 109 cm. Total 
period of Observation 46 days. 
In tbe light this shoot would have made the diageotropic 
curve at a hight of 15 cm to 20 cm. 
The following is an example of 4 shoots which were never 
exposed to the light, which were not observed closely for details 
of nutation, bnt were followed in their later behavior to see 
whetlier they would adopt a constant direction of growth: 
5) Shoot remained orthotropic for 18 days after appearing 
above ground, being then 23 cm tall. Matnre assimilating shoots 
next older than one in the opaque cone averaged 21 cm yertical 
portion. From the beginning on thrn a total period of 150 days, 
the shoot made a total growth of 177 cm, the tip then dying and 
a lateral brauch being sent ont later which continued the growth. 
Düring the whole period, after the first 18 days, the tip of the 
main axis alternately declined from 45° to 70° and rose to the 
yertical, remaining never more than a few days (1 to 8) in one 
Position. The record shows the tip was yertical when the shoot 
was 48 cm tall, 61 cm, 79.5 cm, and 172 cm. The last hight 
was attained only 8 days before the death of the tip. 
3. Behavior of shoots exposed to light for one to 
several days. As clearly as the experiments illustrated by the 
foregoing exampies demonstrate the inability of the plant in the 
absence of light to retain its plagiogeotropism, after relinquishing 
its negative geotropism, not less clearly does another set of ex¬ 
periments demonstrate the specific ability of light to make per¬ 
manent this diageotropism even when light is cut of for days before 
the plant shows this reversal of response. This series of experiments 
has included the study of tbe behavior of 21 shoots of Asparagus 
from which light has been excluded after these shoots had been 
exposed to light from one to many days. The shoots were selected 
for exclusion from the light after they had attained various hights 
varying from 1 mm above ground to 8 cm above ground, the latter 
size belonging to shoots which were nearly ready to begin the 
diageotropic curve. The preparations were kept in the dark-room, 
or opaque covers as paper cones were used as in the former set 
of experiments, the assimilating shoots in the same pots being 
allowed to continue their functions. Representative experiments 
are given here. 
6) Pot with a young shoot 8 cm above ground was removed 
from greenhouse to dark-room. Tip was already nutating pre- 
paratory to going to the transverse position. First day in dark, 
tip kept vertical position — second day, tip declined to 25° from 
yertical — after some nutation, tip reached the horizontal position 
on 4th day after placing in dark-room, held this position per- 
manently and unfolded its branches, including needles. 
7) Shoot 7 cm tall when covered — in the dark erect for 
3 days — then declined 30° when 11 cm tall — 5th day declined 
to 35° — 7 th day decliged to80° — 8th day declined to 90° — 
