REVIEWS OF RECENT LITERATURE. 
Animal Psychology.'— Every book which comes to us from the 
direct and faithful observer of psychical development in the lower 
animals is doubly to be welcomed: first, for our abiding interest in 
them which makes every trait of theirs worth knowing for its own 
sake ; and, second, for the light which a study of their nature throws 
upon the problems of human psychology. Among the latest of these 
contributors is Prof. Wesley Mills, of McGill University, Montreal, 
who has been known for a score of years as a successful breeder of 
dogs and a close student of the habits and development of this and 
allied species of animals. The book consists of four parts. The 
first of these comprises a group of essays and addresses upon the 
methods and the value of Comparative Psychology; the second deals 
with the phenomena of hibernation, feigning and allied states among 
animals, and with analogous states obtaining in human subjects ; the 
third and most important section of the work consists of detailed 
original observations upon the physical and psychical development of 
animals, supplemented freely by constructive criticism ; and in the 
fourth is added the reprint of a series of discussions upon the nature 
of instinctive tendencies, which appeared originally in Science, 1896. 
The papers which form the preceding parts of the book were first 
published in Science, Popular Science Monthly, and other periodicals, 
and in the Zransactions of the Royal Society of Canada. 
Professor Mills comes to his work well fitted by years of patient 
and direct study of animals in his own warrens and breeding kennels ; 
and only such work as his will be of final value for the science of 
animal and comparative psychology. ‘Closet psychology,” he says, 
“cannot hope to accomplish much.” “He who would understand 
animals thoroughly must live among them, endeavor to think as they 
think and feel as they feel, and this at every stage in their develop- 
ment.” 
At the outset the author makes plain his conception of the impulse 
to animal study and the nature of its problems. Our interest is based 
: 1 Mills, Sead M.A., M.D., F.R.S.C., etc., Professor of Physiology in McGill 
-o University, M treal, Canada. The Nature and Development 7 Animal Intelli- 
m The Macosiltan pees en 8vo., PP- 3o ; 
