x PREFACE 
“Animal Intelligence and how to Study It,” 
appeared, in the first instance, in The Sherbrooke 
Examiner; “Comparative Psychology,” etc., in Appletons’ 
Popular Science Monthly ; “ Psychology and Comparative 
Psychology,” in Science ; “Squirrels: their Habits and 
Intelligence,” etc., and all the papers following, as far 
as page 276, in the Transactions, Royal Society of 
Canada; the “ Discussion on Instinct,” ete., in Science. 
I desire to offer my thanks to the Editors and 
Publishers of the before-mentioned periodicals for 
their courtesy in readily assenting to re-publication 
of the papers referred to, as also to those contributors 
who have kindly allowed me to embody their views in 
this book. 
As the discussions in Part IV. are printed just as 
they originally appeared, perhaps it may be well to 
state that Professor Morgan’s views on the subjects 
under consideration may be found fully developed 
in his “Habit and Instinct,’ and Professor J. Mark 
Baldwin’s in papers that have appeared in the 
American Naturalist, Science, and the Psychological 
Review, though such contributions cover a wider 
field than that traversed in the discussions to which 
reference is now made. 
THE AUTHOR: 
