PREFACE 



It is desirable, perhaps, to give some reason for adding 

 another book on Natural History to the many that already 

 exist, and to indicate in what way the book is intended to 

 be used. 



The danger of the multiplication of small text-books is 

 that they may conceivably be used in place of that first-hand 

 investigation which must form the basis of all scientific work ; 

 nevertheless, so long as the time allotted to Natural History is 

 as limited as it is in the ordinary curriculum of school and 

 college in this country, it is necessary to use to the best 

 advantage the hours which teacher and pupils spend together, 

 and I suggest that this time can at first be most profitably 

 spent in practical work, during which the teacher directs and 

 supplements the observations of the class, leading his pupils 

 to reason about the facts they observe, and to record them by 

 means of clear accurate drawings with brief explanatory notes. 



This method, hoAvever, leaves little time for ordinary note- 

 making in which the facts are woven into a coherent whole 

 that may be used for future reference and revision ; and it is 

 partly for this reason that I venture to think there is room 

 for such a book as this, which, as well as giving directions 

 for the practical study of a number of different types of 

 living animals, gives also a general account of their structure 

 and life-history, and indicates their relationship to other 

 creatures so that they do not remain as isolated types in the 



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