PREFACE. xi 



now becomes light and instructive. So it is that by patience 

 and perseverance the student learns how to observe those letters 

 of antiquity, and to comprehend their value and significance, 

 and to combine them into words and sentences and discourses, 

 while others who have not thus trained themselves, can see noth- 

 ing but chips and fragments and scratches. 



The geologist, too, is patiently learning the language of the 

 rocks and the drift, written long ages ago, which can alone be 

 interpreted by comparing fact with fact, each of which, when 

 well authenticated, is a new word in this new language, in which 

 nature tells the story of what once was and the changes she has 

 wrought in bringing her works to their present state. So must 

 the lessons of all the sciences be studied before they can meet 

 the demand for knowledge made by the advancing standard set 

 np by the inquiring mind of this our day, which we may well 

 anticipate, will be greatly elevated in the immediate future. 



If zoology is among the oldest of the natural sciences it is 

 among the lowest in its standard of fullness and exact observa- 

 tions, and yet without these we can never hope to an-ive at 

 correct conclusions. In this work, by confining myself to a 

 few objects, I have thought it possible to go beyond my prede- 

 cessors in the accumulation of facts, hoping that others may take 

 np other divisions of the subject and treat them so thoroughly as 

 to leave nothing to be desired, till at last the whole subject will 

 be so wrought in detail that the generalizer will find in his hands 

 abundant material for his part of the work. His great want 

 now is well attested facts. These I have attempted to give 

 without adornment as to the animals treated of. In preparing 

 ray illustrations, I have tried to make them true to nature, re- 

 gardless of the question whether they were ornamental pictures 

 or not. In the full figures I have as far as possible drawn from 

 photographs, taken when the animals were standing at ease, be- 

 lieving that in this way I could give a truer idea of them than 

 if they were made to assume striking and unusual attitudes, 

 which might be more attractive to the eye. If my animals differ 

 in position and appear less elegant in form than the same ani- 

 mals are generally represented in books and in paintings, I can 



