24 D. B. CASTEEL 



fested itself throughout a turtle's performances and was char- 

 acteristic of the animal. There were a few exceptions to this 

 general rule, cases of sulkiness or sluggishness resulting from ill 

 health or too frequent punishment. 



The tendency toward right or left turning was of frequent 

 occurrence during the course of the experiments. Some turtles 

 never acquired it, others for a short time only, but in most cases 

 when it once became established its permanency was assured. 

 The writer has no explanation to offer for the initial cause of 

 such a habit, but merely suggests that once such a tendency 

 is well started its continuance is assured by the potency of 

 kinaesthetic sensation and association. Yerkes' long ago showed 

 the facility with which land tortoises learn the windings of a 

 simple maze, and in some early experiments with Chrysemys I 

 obtained results which indicate that this water turtle learns 

 such problems with comparative ease. As Watson'' has shown 

 for the rat, the ability of an animal to learn a maze is largely 

 dependent upon the kinaesthetic sense,-- it is a matter of mus- 

 cular appreciation of distance and direction. Once it is estab- 

 lished all other senses are subordinate to it. In the same way 

 it may be supposed that once a tendency toward turning in the 

 direction of a right or left box is (for some unknown reason) 

 established, it will tend to persist even though other senses 

 warn against such procedure. 



Mental instability. The mind of the turtle is erratic. A 

 glance over the tables will show instances of pronounced failure 

 closely following successful tests. One day the turtle will be 

 near perfection and upon the next will record a series of failures. 

 Such lapses may occur well toward the end of a series of tests 

 otherwise excellent. I am convinced that these seasons of 

 forgetfulness would continue to occur at irregular intervals no 

 matter how long the training of the animal was continued. With 

 any animal whose mental capabilities are no more highly devel- 

 oped than those of the turtle it is scarcely to be expected that 

 attention to the problem at hand will always be alert or that 

 memory will always serve as a reliable guide. 



^Influence of former experiences. Much has been written of 

 recent years regarding the influence of past experiences upon 

 animal behavior, and of the necessity of a thorough acquaintance 

 with the past histories of animals subject to experiment. One 



^Yerkes, R. M., The Formation of Habits in the Turtle, Pop. Sci. Mo., 1901, 

 vol. 58, p. 519. 



* Watson, J. B., Kinaesthetic and Organic Sensations: their role in the reactions 

 of the white rat to the maze. Psych. Rev. Monograph Supp., 1907, vol. 8, No. 2. 



