The Lite of the Caterpillar 



theory that odorous effluvia serve as a guide 

 to the Moths invited to the nuptial feast. 

 That I did not do so was due to a casual ob- 

 servation. The unexpected, the fortuitous, 

 often provides us with one of those surprises 

 which show us the road to the truth, hitherto 

 sought in vain. 



One afternoon, trying to discover whether 

 sight plays any part in the search, once that 

 the Moths have entered the room, I place the 

 female in a glass bell-jar and give her a little 

 oak-branch, with withered leaves, as a perch. 

 The apparatus is put on a table, opposite the 

 open window. On entering, the Moths can- 

 not fail to see the prisoner, standing as she 

 does where they are bound to pass. The pan 

 with its layer of sand, in which the female 

 spent the previous night and the morning un- 

 der a wire-gauze cover, is in my way. I put 

 it, without premeditation, on the floor at the 

 other end of the room, in a corner which is 

 only dimly lighted. It is seven yards from 

 the window. 



The result of these preparations upsets all 



my ideas. Of the Moths arriving, none stops 



at the glass bell, where the female is plainly 



visible, in the full light. They pass by with 



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