444 ANDREWS AND ELLIs: REACTIONS OF HAIRS OF SALVINIA 
In jar Number 1 the Salvinia was floated on distilled water. 
In jar Number 2 on a nutrient solution containing the following 
substances: 
ere WE ee ae eee eis Oh oy eee 1000.0 cc. 
WO cust Niet ie 2k en Pd ke PR es I.0 gm. 
RCOPCTE SUMO MDLG 20's Sidiice. Wee cds Se aCe 0.5 gm. 
PAA PCH BIN DUALE i <6. ook lc cs eae oe ce oa 0.5 gm. 
PICS FINOM PALE oak ais ee bk et aia 0.5 gm. 
Jar Number 3 contained a nutrient solution the same as that 
used in Number 2, except that the potassium nitrate was omitted. 
On the leaves of the Salvinia in this jar were placed cubes of cooked 
white of egg, drops of uncooked white of egg and crushed insects. 
Jar Number 4 also contained a nutrient solution the same as 
Number 3, that is, without the potassium nitrate, but the leaves 
in this jar were free from foreign substances. | 
The Salvinia in jar Number 1 began to change color on the 
second day. The otherwise bright green color of the leaves be- 
came dull and by the fifth day there were distinct yellow spots 
on the leaves. In a week all of the leaves in this jar were of a 
uniform brownish-yellow color. In Salvinia care must be taken 
to keep the light conditions for good growth as nearly constant 
as possible. It frequently happens that Salvinia plants that 
have been growing in somewhat weak light will, when brought into 
very bright light, lose their green color and die. This, however, 
may be prevented by gradually bringing them into strong light 
which they may then stand without the least i injury. 
The plants in jar Number 2 remained quite normal throughout 
the entire experiment, which lasted fifteen days. 
The leaves in jar Number 3 began to lose their color in six 
days and those in Number 4 four days. Both those with and 
without foreign matter on them finally lost all their color. By 
the end of the first week, however, there was a decided difference 
between the leaves in the two jars. Almost all of the leaves in 
both jars were turning yellow but those in jar Number 3 retained 
their color, especially, in the area immediately around that 
covered with organic matter. The ninth day all the leaves in 
both jars were yellow, excepting a few in jar Number 3. These 
few were still a little green in the area around the organic matter. 
