THE ADVENTURES OF A GRUB 



Sitaris, the Beetle whose corpses appear in such quan- 

 tities on the surface of the bank. 



If the layer of Osmia-cells be removed from the nest 

 we can observe the cells of the Anthophora. Some will 

 be occupied by larvae, some by the perfect insect, and 

 some indeed many will contain a singular egg-shaped 

 shell, divided into segments with projecting breathing- 

 pores. This shell is extremely thin and fragile; it is 

 amber-coloured, and so transparent that one can dis- 

 tinguish quite plainly through its sides a full-grown 

 Sitaris, struggling as though to set herself at liberty. 



What is this curious shell, which does not appear to 

 be a Beetle's shell at all? And how can this parasite 

 reach a cell which seems to be inaccessible because of 

 its position, and in which the most careful examination 

 under the magnifying-glass reveals no sign of violence? 

 Three years of close observation enabled me to answer 

 these questions, and to add one of its most astonishing 

 chapters to the story of insect life. Here is the result 

 of my inquiries. 



The Sitaris in the full-grown state lives only for a day 

 or two, and its whole life is passed at the entrance to 

 the Anthophora's galleries. It has no concern but the 

 reproduction of the species. It is provided with the 

 usual digestive organs, but I have grave reasons to doubt 

 whether it actuallv takes any nourishment whatever. 



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