THE HABITS OF CERTAIN TORTOISES. 



H. H. NEWMAN. 

 {Contributions from the Zoological Laboratory of the University of Michigan, No. 104-) 



CONTENTS. 



Introductory Remarks 126 



Classified Activities 128 



Aspidonectes spinifer 128 



Graptemys geographica 136 



Chrysemys marginata 143 



Aromochelys odorata 145 



Chelydra serpentina 149 



General Summary 152 



INTRODUCTORY REMARKS, 



Methods of Study. — In order to understand an animal one must 

 live with it, must spend long hours, quiet days, in thoughtful 

 observation of it, as it pursues its daily round of occupations. 

 This I have had an opportunity of doing, and I now feel that I 

 have a really personal acquaintance with at least five species of 

 tortoises. I believe that I am able to diagnose their dispositions 

 and comparative intelligence — their character. 



Not only is there a species character but a sex character and 

 even an individual character. For example, males are, as a rule, 

 more timid than females, and specimens of the same sex and age 

 often show marked individual differences in disposition. 



Studies of this sort should, I believe, precede experimental 

 studies, for sometimes shyness or wariness might be mistaken for 

 stupidity, and sullenness for sluggishness in reaction. As a rule 

 the more highly organized and alert species of tortoises display, 

 when in captivity, the greatest degree of sullenness and hence 

 their actions in confinement very poorly represent their true 

 character. The species, on the other hand, that are less 

 highly organized are the species that act more nearly normally 

 when in captivity; but these naturally stupid forms furnish the 



