BRITISH BUTTERFLIES 



knows from experience exactly where he is likely to 

 find any species which he may require, he is, in the 

 majority of cases, quite unable to account for the 

 creature's predilection for that particular locality. 



What is that you say ? You understand now why 

 these creatures indulge in aeronautical excursions. 

 You think that they leave because the district is not 

 in accordance with their tastes. Without being in any 

 way pedantic, and without forgetting the caution which 

 a long acquaintance with Nature's curious methods has 

 engendered, I am afraid I must again disagree with you. 

 You must remember that the mother spider makes 

 strenuous efforts to place her eggs in such a position that 

 the young spiders, when born, shall be under those condi- 

 tions most conducive to their well-being. Why, then, 

 should her offspring reject her choice of a home for 

 them and wander far and wide in search of something 

 better ? Let me hazard an explanation. The patch 

 of herbage at our feet, as you can see for yourself, 

 seems in every way to fulfil the Erigone's idea of a 

 suitable abode, judging from the fact that in practically 

 every tuft of grass there is to be found one of these small 

 beings resting beneath its frail horizontal saucer-like 

 snare. Think, now, what will be the history of this 

 small patch during the coming season. Within a 

 couple of months the female spiders will have deposited 

 their eggs, and leaving them to the mercy of the world 



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