APPENDIX 



THE GEOMETRY OF THE EPEIRA's WEB 



F FIND myself confronted with a subject 

 *- which is not only highly interesting, but 

 somewhat difficult: not that the subject is 

 obscure; but it presupposes in the reader a 

 certain knowledge of geometry: a strong 

 meat too often neglected. I am not ad- 

 dressing geometricians, who are generally 

 indifferent to questions of instinct, nor entomo- 

 logical collectors, who, as such, take no 

 interest in mathematical theorems; I write for 

 any one with sufficient intelligence to enjoy 

 the lessons which the insect teaches. 



What am I to do? To suppress this 

 chapter were to leave out the most remarkable 

 instance of Spider industry; to treat it as it 

 should be treated, that is to say, with the 

 whole armoury of scientific formulae, would be 

 out of place in these modest pages. Let us 

 take a middle course, avoiding both abstruse 

 truths and complete ignorance. 



Let us direct our attention to the nets of 

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