2 INTRODUCTION 
Hence we find among writers of the period mentioned a 
tendency to interpret the actions of animals as the outcome 
of highly developed psychical faculties, and to accept rather 
too uncritically stories indicative of great sagacity on the 
part of animals with the end of showing that the brute 
creation does not stand so very far below us after all. The 
works of Romanes on Mental Evolution in Animals and 
Animal Intelligence are typical of the period and its tenden- 
cies toward anthropomorphism, which is now the béte noir 
of every dabbler in the subject of animal behavior. While 
Romanes has been criticized with a certain amount of 
justice for basing conclusions on anecdotes from more or 
less questionable sources he has the merit of bringing to- 
gether a large number of facts regarding animal intelligence 
and of giving an able and lucid account of the general course 
of mental evolution, and there is no doubt that had his 
life extended into the period of more careful and accurate 
experimentation he would have been among the first to 
appreciate and encourage the newer animal psychology. 
The advent of experimental psychology with its various 
appliances for observing and recording the manifestations 
of mental phenomena, the study of the functions of the 
nervous system by the experimental methods of the phy- 
siologists, and the growing vogue of methods of experimental 
analysis in biology in general could not fail to have a marked 
influence on the study of the mental life of animals. After 
the scientific world had comfortably settled down in the 
belief in continuous mental evolution, and the subject had 
mainly lost its controversial interest, attention became more 
strongly directed to the analysis of animal behavior with the 
end of explaining why animals act as they do. Then came 
the period of reflexes and tropisms and the analysis of com- 
plex behavior into simpler processes, with which we are now 
