PKEFACE. vii 



not a doubt that, for the present generation at all events, 

 no subject of scientific inquiry can present a higher 

 degree of interest; and therefore it is mainly with the 

 view of furthering this inquiry that I have undertaken 

 this work. It will thus be apparent that the present 

 volume, while complete in itself as a statement of the 

 facts of Comparative Psychology, has for its more ultimate 

 purpose the laying of a firm foundation for my future 

 treatise on Mental Evolution. But although, from what I 

 have just said, it will be apparent that the present trea- 

 tise is preliminary to a more important one, I desire to 

 emphasise this statement, lest the critics, in being now 

 presented only with a groundwork on which the picture is 

 eventually to be painted, should deem that the art dis- 

 played is of somewhat too commonplace a kind. If the 

 present work is read without reference to its ultimate 

 object of supplying facts for the subsequent deduction of 

 principles, it may well seem but a small improvement 

 upon the works of the anecdote-mongers. But if it is 

 remembered that my object in these pages is the mapping 

 out of animal psychology for the purposes of a subsequent 

 synthesis, I may fairly claim to receive credit for a sound 

 scientific intention, even where the only methods at my 

 disposal may incidentally seem to minister to a mere love 

 of anecdote. 



It remains to add a few words on the principles which 

 I have laid down for my own guidance in the selection and 

 arrangement of facts. Considering it desirable to cast as 

 wide a net as possible, I have fished the seas of popular 

 literature as well as the rivers of scientific writing. The 

 endless multitude of alleged facts which I have thus been 

 obliged to read, I have found, as may well be imagined, 

 excessively tedious ; and as they are for the most part re- 

 corded by wholly unknown observers, the labour of reading 



