208 
FOURTEENTH REPORT. 
troduced simultaneously with the food as an associated or non-essential 
stimulus, and a record made of the number of reactions occurring after 
the withdrawal of both, in a given number of tests. The element of 
disturbance was found to be very great because of the viscidity of the 
secretion of mucous on the foot and the consequent adhesion of the 
apparatus. For this reason the mechanical stimulus for a time inhibited 
the unconditional reflex. This inhibitory effect gradually wore off, 
■however, and the two stimuli combined gave a record showing a smaller 
number of reactions than normal but averages with no greater varia- 
tions. 
(3) If an association between food and pressure has been established 
the effect of the association should appear when the non-essential stimu- 
lus is employed, that is, for example, when pressure is applied with- 
out food. TIi is proved true in G2!/2% of the cases tried. 
(4) and (5) are not yet in a condition to be reported upon. 
The actual work has only been fairly started so that the results thus 
far obtained are not definite enough to justify the formulation of con- 
clusions. The methods employed were suggested by the Pawlow Salivary 
Reflex Method in Animal Psychology. Pawlow's method commends it- 
self because of its absolute precision although applicable to a limited 
group of animals. It is believed that work on behavior on any given 
group of animals might be placed on a similar physiological basis if a 
measurable reflex could be discovered. 
Fig. 1. Apparatus used to introduce food and pressure simultane- 
ously. 
A. handle; P>. steel needle; C Food hook; 
of water; F, snail. 
1 >. pressure bar; E, surface 
