Bramble-bees and Others 



Well, these short tubes, whether of glass 

 or reed, were seized upon as eagerly as the 

 long tubes. Moreover, they yielded this 

 splendid result: their contents, only a part 

 of the total laying, always began with female 

 and ended with male cocoons. This order was 

 invariable; what varied was the number of 

 cells in the long tubes and the proportion be- 

 tween the two sorts of cocoons, sometimes 

 males predominating and sometimes females. 



The experiment is of paramount import- 

 ance; and it will perhaps make the result 

 clearer if I give one instance from among 

 a multitude of similar cases. I give the pref- 

 erence to this particular instance because of 

 the rather exceptional fertility of the laying. 

 An Osmia marked on the thorax is watched, 

 day by day, from the commencement to the 

 end of her work. From the ist to the loth 

 of May, she occupies a glass tube in which 

 she lodges seven females followed by a male, 

 which ends the series. From the loth to the 

 17th of May, she colonizes a second tube, in 

 which she lodges first three females and then 

 three males. From the 17th to the 25th of 

 May, a third tube, with three females and 

 then two males. On the 26th of May, a 



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