Some observations concerning the reactions of the leaf hairs of 
Salvinia natans 
FRANK MARION ANDREWS AND Max Mapes ELLIS 
If one observes plants of Salvinia natans which are in an active 
condition, it will be observed that the hairs on the leaves show 
drops of liquid which they secrete. It was noticed from time to 
time that some of the leaves of the Salvinia which was kept growing 
in a large tub in the green-house bore small drops of dark colored 
liquid. Frequently a dead dipterous insect was found on the 
surface of a leaf somewhat enveloped in a white fiingus which was 
also attached to the leaf hairs. These occurrences coupled with 
the superficial resemblance of the leaves of Salvinia to those of 
Drosera suggested the possibility that this fern might also be able 
to absorb food from decaying matter on the leaves. It was first 
desirable to see if organic matter would go into solution on the 
leaves of this plant. 
Experiment 1. Two large battery jars of Salvinia were iso- 
lated from the tub and small soft-bodied dipterous and thysanuran 
insects, such as were found in and about the tub, were crushed and 
placed upon many of the leaves. By the end of a week all of 
these insects were covered with a white fungus, apparently the 
same as that previously noted on the Salvinia in the tub. During 
the second week almost all of this fungus disappeared and most 
of the inserts were reduced to drops of dark colored liquid. Onlya 
few of the insects dried up. This experiment makes it entirely 
probable that some of the dark colored drops found on the leaves 
of the Salvinia in the tub contained organic remains. This reduc- 
tion of the organic matter to a solution may have been the result 
of any or all of these three actions, (1) simple decomposition, (2) 
action by the Salvinia or (3) action by the fungus. Three experi- 
ments were made to ascertain whether or not the Salvinia con- 
tributes to this decomposition of the organic matter. 
Experiment 2. Several large crystallizing dishes were filled 
with fresh Salvinia. On the surface of about every other leaf 
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