The Glow- Worm and Other Beetles 



pairing-time. Wings and flight there will 

 be none : the female retains her humble larval 

 form, but she kindles her blazing beacon. 



The male, on his side, is fully transformed, 

 changes his shape, acquires wings and wing- 

 cases; nevertheless, like the female, he pos- 

 sesses, from the time when he is hatched, the 

 pale lamp of the end segment. This lumin- 

 ous aspect of the stern is characteristic of 

 the entire Glow-worm tribe, independently 

 of sex and season. It appears upon the bud- 

 ding grub and continues throughout life un- 

 changed. And we must not forget to add 

 that it is visible on the dorsal as well as on 

 the ventral surface, whereas the two large 

 belts peculiar to the female shine only under 

 the abdomen. 



My hand is not so steady nor my sight so 

 good as once they were, but, as far as they 

 allow me, I consult anatomy for the structure 

 of the luminous organs. I take a scrap of 

 the epidermis and manage to separate pretty 

 neatly half of one of the shining belts. I 

 place my preparation under the microscope. 

 On the skin, a sort of white-wash lies spread, 

 formed of a very fine, granular substance. 

 This is certainly the light-producing matter. 

 To examine this white layer more closely is 

 beyond the power of my weary eyes. Just 

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