186 MANTON COPELAND 
The tentacles of a slowly moving snail were touched ten times 
with each of these pipettes, the trial with the fish extract always 
following that with sea water. The stimulating agent was 
applied to the right and left tentacle alternately. In four in- 
stances the cotton flooded with sea water excited no response; 
once the proboscis was momentarily extruded; and in the re- 
maining trials the snail usually turned slightly toward the 
cotton, sometimes bending the siphon in its direction, and 
continued its course. Some slight coiling of the ends of the 
tentacles was also observed, and once the snail stopped moving 
after stimulation. 
When the cotton flooded with fish juice was applied to the 
tentacles, the reaction was quite different and similar to that 
obtained by squirting the fluid on these organs. They con- 
tracted and coiled, the siphon was bent toward the cotton and 
the animal turned in the same direction, often following it the 
greater part of a circle. Finally, the proboscis was extended 
in the direction of the juice. The proboscis reaction occurred 
in every trial. 
The foot. The sensitiveness of the lateral and posterior borders 
of the foot was tested by the same methods. A stream of sea 
water containing dry carmine, when applied as gently as possible 
to the side of the foot of a moving animal, caused either no visible 
response or a slight local contraction at or behind the spot first 
stimulated. Sometimes the contraction wave passed posteriorly, 
causing a lifting or withdrawal of the edge of the foot. Fish 
extract and carmine, on the other hand, induced a well marked 
local contraction, often resulting in a lifting of the border of the 
foot, the raised area extending backward until the posterior 
end of the foot was free from the glass. Once or twice the con- 
traction wave ran forward, causing a lifting of the antero- 
lateral border of the foot. 
When the extract was applied to the posterior end of the foot 
of a moving snail, the response was also well marked. The end 
of the foot for a distance of two or three millimeters, or less, was 
lifted from the glass and perhaps slightly contracted. This reac- 
tion very seldom occurred when sea water and carmine were used. 
